NEED HELP 02 EXT LT, P1860, P740, P753, P758, P785. Under-hood fuse #34 blown

Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
I’m in DESPERATE need of help here.
My poor Trailblazer (wife nicknamed it Bertha) has been sitting in the back yard untouched for over a month now because I can’t get to the bottom of this.
The story goes; I went on an hour long journey to get a part for an unrelated project. The drive went perfectly fine right up until the exact moment I entered the parking lot at the establishment I was trying to reach. All of a sudden I heard my subwoofer thump just a little for like a spilt second. It always thumps like that when I start the engine, but never any other time. At the same time I smelled a burning electrical smell and it was gone as quickly as it came. When I parked a few seconds later I turned the engine off, afraid the whole thing may go up in smoke. I couldn’t remove the key from the ignition nor start the engine back up. No click or anything. When I turned the key to start the engine like normal everything on the dash just goes away, no lights or gauges, and the fuel and battery gauge drop to zero when the key is turned to start. I can’t remember if it’s always done that when starting or not. I cleaned my battery terminals as I’ve had trouble with them before but to no avail. A Good Samaritan tried to give me a boost, I figured it wouldn’t hurt to try but nothing Changed at all. I was not listening to any music at the time, in fact my radio was turned off so I know it’s not something with my amp or anything. A quick google search told me how to remove my key, I pressed the emergency key release button and I walked 1.4 miles to the nearest autozone and got an ignition switch as I was familiar with the common failures, I replaced it right then, no change. I walked another 1.4 miles then replaced the main fuse at the under hood fuse box, no change. I spent the next hour and a half it was going to take for the wife to come pick me up checking every single fuse on both fuse panels (yet somehow overlooked the J-Case fuses)
This caught me very off guard, however I did have a weird problem before a while back where my starter would stay stuck trying to turn the engine over even if the engine was already running, kind of like a “runaway” starter, and the only way to stop it was to move the purple wire that goes on the starter. It was caused by the hooked part on the purple wires’ ring terminal touching the much bigger copper terminal on the starter, it would happen randomly but I tinkered with it over time and thought I had fixed it but I believe this starter problem had occurred when I was turning into the parking lot that day. It’s worth mentioning that I smelled that same brief burning electrical smell every time my starter would get stuck like that but it had been so long since I thought I fixed it, that I started to panick.
Furthermore; upon trying to diagnose the issue I’ve found that J-Case Fuse #34 (IGN A 40a) in the under hood fuse panel will blow every time I turn the key to RUN. I’ve also learned that this circuit pretty much provides power to all of the shift solenoids and the TCC/PWM which is why I’m getting these codes. I have been able to drive it after this incident but the only way to start it is by intentionally arching the purple wire to the bigger post on the starter as explained before while someone is turning the key to start. Also while driving it, it is stuck in 3rd or 2nd gear, can’t really tell which. Everything else works fine as far as driving goes but it will not shift on its own and it will not start on its own.
I guess what I really need to know is where the hell do I even start with the short at fuse #34? I’ve looked at wiring diagrams but I’m having a consistency issue between each one I see regarding where it says the wires go. I don’t want to just start blindly tearing into my wiring harness or fuse block and end up with spaghetti that I will never be able to fix.
Has this happened to anyone else? I’m tired of driving my wife’s little 14’ Cruze, I want my trailblazer back! Not to mention it’s also hurting my business severely as I use my trailblazer to pull a trailer for my work. So needless to say I’m starting to go broke too! I need some GMT gurus to please help me!

PS: I’ve watched MAY03LT’s video on this issue and while it does pertain to the issue somewhat, mine is different in the fact that I can’t get power to the fuses I need to check in my rear fuse block because the fuse in the under hood fuse block that supplies power to it is blowing every time I turn the key to run. So I’m sure everything to and from there is fine, but something to or from fuse #34 is not fine and that’s what I’m needing help with, and I can’t find ANYTHING about this anywhere, so here I am!
 

TollKeeper

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Dec 3, 2011
8,045
Brighton, CO
My suggestion would be a narrowing of the problem. Grab your camera phone, take a really good picture of your front fuse panel, or even multiple. Then pull every single fuse out of the fuse panel, including mega fuses. Just leaving the relays. Now put in that fuse that blows every time you turn on the ignition. Turn on the ignition. Did the fuse blow? If not, slowly, put 1 fuse in the fuse box at a time, waiting about a minute inbetween fuses. Sooner or later your going to find the circuit that causes the fuse to blow. If it did blow, you have reached the limit of my skill, unless its something related to the rear fuse panel, and you can perform the same process for that fuse panel.

I would also go under your steering column, above your knee bolster. Check all the wiring, making sure the previous owner didnt cobble up some sort of remote start, and cut wires that should not have been. This is a very common problem of remote starters installed by techs that have no business touching wiring.
 

TJBaker57

Member
Aug 16, 2015
2,897
Colorado
I would try to isolate the bad circuit causing the overload.

Download literature here......

Study the power distribution wiring diagrams. Try removing all the fuses fed by fuse 34 then turn the key to RUN and see if fuse 34 holds. Add back fuses one at a time working from the largest rated fuse to the lowest and see when fuse 34 blows. This might help in locating the bad circuit.
 
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mrrsm

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Oct 22, 2015
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Tampa Bay Area
This may turn out to be a "Self Inflicted Wound":

Judging from all of your Mods... Taking ALL of them back down to "Zero" and trying to ensure that NO Electricity is feeding ANY of these AM Components would be a good place to Start:

2MANYMODZ.jpg
 
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Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
This may turn out to be a "Self Inflicted Wound":

Judging from all of your Mods... Taking ALL of them back down to "Zero" and trying to ensure that NO Electricity is feeding ANY of these AM Components would be a good place to Start:

View attachment 98709
I’m very experienced in installing car audio, I have completely disconnected everything aftermarket and nothing has changed, just like I had anticipated.
 

mrrsm

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Oct 22, 2015
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Of course...just as indicated in your Profile... However, even with your understanding of these Electrical systems and capabilities of running Good Diagnostics and Repairs, if you either live in a Rural Area... or have only driven "Bertha" occasionally... Inexplicable Electrical problems might have an "external" cause that is 'plaguing' your electrical system that you might not ordinarily think about:

Rodents

These animals might be "The Culprits"...in particular the Genus and Species of the Ubiquitous "Deer Mouse":

DEERMOUSE.jpg

These numerous animals can become more than a a mere nuisance from their incessant need to Chew, Gnaw and Wear Down their Endlessly Growing Incisors upon something like Insulated Wiring and Plastic Connectors. They can also become Quite Dangerous to Humans as they are the primary vectors and transmitters of the invariably fatal "Hanta Virus".

These rodents can form hidden nests under the hoods and engine nacelles and live in nearby wooded areas. On Cold Nights, they can climb up and inside of Engine Compartments in order to warm themselves on recently run Engines. In doing so, they can invariably Chew on the Wiring and also leave traces of the "Hanta Virus" in their desiccated Urine and Feces around these Nesting and Hiding Areas.

If these friable dried particles become disturbed and airborne... they can be inhaled into the Lungs and develop into a form of Hemorrhagic Fever that can KILL you. So Please... Mask and Glove up if you raise your Engine Hood and find traces and/or artifacts of their presence that look anything like THIS:

20200212_082334.jpg20200212_082029.jpg20200212_084141.jpgVideoCapture_20200212-083951.jpgVideoCapture_20200214-163628.jpg
 
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budwich

Member
Jun 16, 2013
2,027
kanata
I would try to isolate the bad circuit causing the overload.

Download literature here......

Study the power distribution wiring diagrams. Try removing all the fuses fed by fuse 34 then turn the key to RUN and see if fuse 34 holds. Add back fuses one at a time working from the largest rated fuse to the lowest and see when fuse 34 blows. This might help in locating the bad circuit.
X2 the fuse feeds about 7 "sub circuits". The "funny" thing about the "setup" is that the sub-circuits form over 80 amps worth of "protections" in terms of fusing. Of course, they won't all draw near their fuse limits. One technique for finding a "shorting type" connection is to use a bulb to limit the draw. This saves having to keep replacing a 40 amp fuse which could get expensive. Basically replace the 40 amp fuse with a bulb holder and 12v bulb... the higher rating, the better ( more amps). With all sub fuses pulled, turn the key to run. Observe the brightness of the lamp. With all fuses pulled, it should be off. Then put back one fuse at a time and observe the brightness of the bulb... higher brightness means the subtending circuit is "low impedance / short". My guess right how is your HVAC has a short / near short.
Of course, this is based on looking at a 2002... not sure of your year.
 
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Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
X2 the fuse feeds about 7 "sub circuits". The "funny" thing about the "setup" is that the sub-circuits form over 80 amps worth of "protections" in terms of fusing. Of course, they won't all draw near their fuse limits. One technique for finding a "shorting type" connection is to use a bulb to limit the draw. This saves having to keep replacing a 40 amp fuse which could get expensive. Basically replace the 40 amp fuse with a bulb holder and 12v bulb... the higher rating, the better ( more amps). With all sub fuses pulled, turn the key to run. Observe the brightness of the lamp. With all fuses pulled, it should be off. Then put back one fuse at a time and observe the brightness of the bulb... higher brightness means the subtending circuit is "low impedance / short". My guess right how is your HVAC has a short / near short.
Of course, this is based on looking at a 2002... not sure of your year.
That’s the year it is, 2002. What makes you think the HVAC has a short? Where does that tie in? This is only confusing me more lol
 

Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
Of course...just as indicated in your Profile... However, even with your understanding of these Electrical systems and capabilities of running Good Diagnostics and Repairs, if you either live in a Rural Area... or have only driven "Bertha" occasionally... Inexplicable Electrical problems might have an "external" cause that is 'plaguing' your electrical system that you might not ordinarily think about:

Rodents

These animals might be "The Culprits"...in particular the Genus and Species of the Ubiquitous "Deer Mouse":

View attachment 98737

These numerous animals can become more than a a mere nuisance from their incessant need to Chew, Gnaw and Wear Down their Endlessly Growing Incisors upon something like Insulated Wiring and Plastic Connectors. They can also become Quite Dangerous to Humans as they are the primary vectors and transmitters of the invariably fatal "Hanta Virus".

These rodents can form hidden nests under the hoods and engine nacelles and live in nearby wooded areas. On Cold Nights, they can climb up and inside of Engine Compartments in order to warm themselves on recently run Engines. In doing so, they can invariably Chew on the Wiring and also leave traces of the "Hanta Virus" in their desiccated Urine and Feces around these Nesting and Hiding Areas.

If these friable dried particles become disturbed and airborne... they can be inhaled into the Lungs and develop into a form of Hemorrhagic Fever that can KILL you. So Please... Mask and Glove up if you raise your Engine Hood and find traces and/or artifacts of their presence that look anything like THIS:

View attachment 98738View attachment 98739View attachment 98741View attachment 98742View attachment 98743
That possibility has been bouncing around in my head as well, but I’ve been up, down, under, around, and inside everywhere I can possibly get to and haven’t found any evidence of mice. At this point I’d almost welcome that over whatever is actually going on ..
 

TJBaker57

Member
Aug 16, 2015
2,897
Colorado
Where does that tie in?
You have downloaded the wiring diagrams, right? You have traced the circuits that energize in the RUN position of the ignition switch, right? So you can see the 30 amp HVAC fuse is the first of several that shows in the diagram where power leads away from terminal G of the ignition switch, yes?
 

Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
You have downloaded the wiring diagrams, right? You have traced the circuits that energize in the RUN position of the ignition switch, right? So you can see the 30 amp HVAC fuse is the first of several that shows in the diagram where power leads away from terminal G of the ignition switch, yes?
Yes I have downloaded what I hope is the correct wiring diagrams, and can see everything but can you help clarify things for me? Help nudge me into the right direction? I'm seeing in Figure 44 Power Distribution Circuit (3 of 5) Line G which i believe indicates the circuits that are energized when in the RUN position but I'm not seeing a 30A HVAC fuse until I flip to the next page, and that does not have the line marked "G" like the other one, so either I'm just too ignorant or I'm on the wrong diagram??
 

Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
I just got back from checking several things, I took my under-hood fuse box apart to trace the wires from the starter and the ignition switch. They where easy to find because they're much thicker than the others. All have continuity on my multimeter and Ohms read 0.00 sometimes 0.01 for a second then back to 0.00. I checked the purple wire from the starter for continuity as well and it read the same as the ignition switch wires. I probed the side of fuse 34 IGN A where the short would be (since the other side is 12v constant) and checked for continuity to my ignition switch and all have continuity and ohms read 0.00 as well, also when I turn the key ( battery is unhooked ) the Red, Orange, and Yellow wires at the ignition switch plug all have continuity to fuse 34, so I don't think the short lies in the ignition switch wiring because it all seems to be normal? I may be wrong though.
 

mrrsm

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Oct 22, 2015
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Speaking of the Under-Hood Power Distribution Center...THIS Video might prove useful as long as your ears can stand the strain of listening to Walking Talking Analogue of and "Ichabod Crane... Dragging His Nails across a Slate Blake Board ... every time he SPEAKS..." Nonetheless, the information he provides here is unusual and useful in this instance.

How to Dis-Assemble a Trailblazer Under-Hood Fuse Box to Inspect for Broken Copper Wiring Traces:

 

Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
Speaking of the Under-Hood Power Distribution Center...THIS Video might prove useful as long as your ears can stand the strain of listening to Walking Talking Analogue of and "Ichabod Crane... Dragging His Nails across a Slate Blake Board ... every time he SPEAKS..." Nonetheless, the information he provides here is unusual and useful in this instance.

How to Dis-Assemble a Trailblazer Under-Hood Fuse Box to Inspect for Broken Copper Wiring Traces:

LOL, yeah I watched that before. I’m not sure where the internal wires meet the J case fuses, his video isn’t very clear on that but I can’t tell even with mine in my hands.. is there another layer to this thing? Looks like the J case fuses plug directly into the harness but I know better because I have continuity to several other fuses from #34 across the board..
Digging into this thing more and more just makes me feel like Chevrolet rigged this crap together last second and shoved it out onto the lot hoping it would work xD
 

coolasice

Member
Oct 27, 2013
1,019
Northern Maine
I just got back from checking several things, I took my under-hood fuse box apart to trace the wires from the starter and the ignition switch. They where easy to find because they're much thicker than the others. All have continuity on my multimeter and Ohms read 0.00 sometimes 0.01 for a second then back to 0.00. I checked the purple wire from the starter for continuity as well and it read the same as the ignition switch wires. I probed the side of fuse 34 IGN A where the short would be (since the other side is 12v constant) and checked for continuity to my ignition switch and all have continuity and ohms read 0.00 as well, also when I turn the key ( battery is unhooked ) the Red, Orange, and Yellow wires at the ignition switch plug all have continuity to fuse 34, so I don't think the short lies in the ignition switch wiring because it all seems to be normal? I may be wrong though.
Did you happen to measure resistance to ground? If it's a dead short you might get less than 10 ohms to ground. I would put all fuses except for the large 40a jfuse back in and check resistance to ground measuring from the end of the j fuse with the key in run. If you see a short to ground you can pull fuses one at a time and see which one is shorted.
 

mrrsm

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Oct 22, 2015
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It appears that instead of going with a much more expensive "Solid State" Breadboard Design... with Fuse and PDC Blocks, GM opted for using "Bent Copper Wires" as traces that plug into Galvanized or Cadmium Plated Steel Press Fit Slots to make the connections between Two or More Pins...and they allowed for the Non-Insulated Copper Wire Sections in between to be isolated from shorting out by "Plugging Them In" to Plastic Slots or Grooves in between; ostensibly to hold them down from excessive vibrations that would invariably result in having some of the Copper lengths flex hardening at harsh angles and bends and thereby separating over time.

Nonetheless... Some of those Copper Wires WILL Work Harden and Fracture over time and either induce Electrical Arcing or suffer complete breaks in the various involved Circuits. The repairs are easy enough to make... as long as you are Tidy with your Soldering Technique. But it will take some time and LOT a VERY Close inspection with a Bright Light and a Magnifying Glass in order to determine any presence of Breaks or Loss of Continuity. Those locations can then be reconnected better with Tin- Lead Mixed Solder and become 'Good as New' afterwards. You know this already, but jik... Please remember to disconnect the Battery (-) Ground Cable before removing the PDC and Fuse Under Box Connectors.
 

budwich

Member
Jun 16, 2013
2,027
kanata
That’s the year it is, 2002. What makes you think the HVAC has a short? Where does that tie in? This is only confusing me more lol
well... I could explain it to you but then I would have to kill you.... :smile:
Actually, looking further, because of the way GM lays out its diagrams, there are a few more subtending circuits. :-(

Anyway, if you want to do the "easy method" and use the " keep replacing the fuse"... that's fine. Again, then the simple test, is to pull at least the "first 7" (which are fuse 47, 50,44,40,29,51,52... at least according to my diagram) and turn the key to run, see if the fuse blows. At that point, you have eliminated at large part of the subtending circuits. Go from the result.

As to why the HVAC, as I mentioned, the "quick sum" of subtending circuits is at least 80 amp on a 40 amp fuse... that means there are lots of things, some small and some large. IF a small draw circuit was exceeding its draw, it would blow the small fuse first.... BUT in your case, although you give us no indication, that has not occurred. That leaves the likely candidate being a large draw circuit as being the prime candidate. .... Bang... you are dead... :smile: Take care... it is always fun chasing electricity.
 
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TJBaker57

Member
Aug 16, 2015
2,897
Colorado
Yes I have downloaded what I hope is the correct wiring diagrams, and can see everything but can you help clarify things for me? Help nudge me into the right direction? I'm seeing in Figure 44 Power Distribution Circuit (3 of 5) Line G which i believe indicates the circuits that are energized when in the RUN position but I'm not seeing a 30A HVAC fuse until I flip to the next page, and that does not have the line marked "G" like the other one, so either I'm just too ignorant or I'm on the wrong diagram??

Seems like we are looking at different diagrams. Here is what I am seeing...

Screenshot_20201120-084639.png
 
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TJBaker57

Member
Aug 16, 2015
2,897
Colorado
I just got back from checking several things, I took my under-hood fuse box apart to trace the wires from the starter and the ignition switch. They where easy to find because they're much thicker than the others. All have continuity on my multimeter and Ohms read 0.00 sometimes 0.01 for a second then back to 0.00. I checked the purple wire from the starter for continuity as well and it read the same as the ignition switch wires. I probed the side of fuse 34 IGN A where the short would be (since the other side is 12v constant) and checked for continuity to my ignition switch and all have continuity and ohms read 0.00 as well, also when I turn the key ( battery is unhooked ) the Red, Orange, and Yellow wires at the ignition switch plug all have continuity to fuse 34, so I don't think the short lies in the ignition switch wiring because it all seems to be normal? I may be wrong though.

Hmmm, I don't mean any offense here... But do you have a firm grasp of what a short circuit is? I ask because the testing for continuity you have done does zero for determining where an overload (possibly a short circuit) that is causing the fuse to blow may be.
 
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Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
Thanks for all the responses guys!
So I think I may have figured it out, my brother came over today and he's much more familiar with this type of thing than I am. The first thing he wanted to do was check the resistance to ground just like @coolasice said. So we hooked the multimeter to both battery terminals (with the battery unhooked of course) and instead of having a steady reading, the readings where all over the place. He said these 2 circuits shouldn't have any impedance between them especially with the battery unhooked, which I knew already, but hadn't thought too much about. This helped narrow down the short to ground SIGNIFICANTLY. Suspecting something was cooked somewhere in this group of wires we started moving and "jiggling" the wires that lead up to both battery terminals to find the bunk wire, immediately we noticed if we moved the starter wire just right, we would get a normal reading. So we disconnected the 4 gauge (or so) wire from the starter as well as the thinner purple wire, and I went ahead and pulled the starter to inspect it (been wanting to do that anyway and today I had time) and I'm very glad I did so.
Turns out the starter solenoid terminal (the copper one that gets the wire straight from the battery) was loose and felt like it wasn't connected to anything inside. We checked for a short to ground from both terminals and sure enough, the starter and the solenoid are both shorted out to the starter body. I have no idea how I was so surprised by this seeing as my key suspicion this entire time was the starter, but now I know for a fact that it is definitely bad, and with such a short in its internals it's probably a safe bet that that's where my short was at this whole time..
when we removed the starter completely, the interference was gone and the readings where as they should be.
 

Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
Bad news... just finished up installing the new starter and .. still blowing fuse 34. Thinking I may just let a mechanic figure this crap out. I haven't got the tools or the knowledge necessary, and quite frankly at this point my give-a-damn is busted.
I guess I'll just keep you guys updated when my mechanic finds something, that way if anyone else ever has a problem like this they will have a good idea what it may be after this issue is resolved.
Now; where's that "SMH" emoji at?
 

budwich

Member
Jun 16, 2013
2,027
kanata
the HVAC is still the best candidate. You were somewhat doing the right thing by measuring resistance at fuse 34.... but you have to be really "good" (accurate) because a 30-40 amp circuit is going to look like a short electrically because 12v / 30 -> is about .4ohms. Most regular meters won't have that great an accuracy to spot a difference there. Again, pull the fuses that were suggested and see if fuse 34 still blows with key on (not start). Anyway, me "give a damn"...mmmeeehhh. :smile: I got to work on my electric starter for my snowblower or get someone to shovel while I read forums... :smile:
 
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Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
the HVAC is still the best candidate. You were somewhat doing the right thing by measuring resistance at fuse 34.... but you have to be really "good" (accurate) because a 30-40 amp circuit is going to look like a short electrically because 12v / 30 -> is about .4ohms. Most regular meters won't have that great an accuracy to spot a difference there. Again, pull the fuses that were suggested and see if fuse 34 still blows with key on (not start). Anyway, me "give a damn"...mmmeeehhh. :smile: I got to work on my electric starter for my snowblower or get someone to shovel while I read forums... :smile:

welp, I tried this method. Fuse still blew. Then Removed all of the fuses and relays except #34 from the entire front fuse panel and the fuse still blew. Tf?
 

budwich

Member
Jun 16, 2013
2,027
kanata
well that isn't necessarily unexpected. It basically indicates that the problem ISN'T likely associated with any circuits down stream (ie. after the fuses) which I guess is kind of expected. As I mentioned, most of the circuits off of that fuse are of lesser value and would have / should have blown before 34. Basically, if you look at the diagrams, your test indicates the problem to be between those fuses outlined and the ignition. NOTE: just to be clear, you are sure you are in the "RUN" position on the switch and that by chance you are NOT in the ACCESSORY position when the fuse blows? This does need to be confirmed.

Once you are sure about the scenario that causes the fuse to blows, The other thing that you might look at is the fuse box itself as there have been posts in the past where some of the underlying tracks / traces have bounded and / or broken. You might to do an inspection of the "connection layer" below the top layer. Having said that, I haven't studied the circuit diagrams fully at this point to see if anything more jumps out.

One more thing... are you sure that you have wired up your starter correctly. One of the few circuits that does not have a fuse directly in the wiring system is the starter. I think you might have crossed the terminals on the starter: red versus purple.... highly likely based on the circuit diagram.
edit: Unlikely to be an issue at the starter as the connectors / bolts probably don't allow a swap of wiring.

Relooking at the starter circuit and related to your earlier posts (about running on starter, jumping wire, etc), it is possible that in the starter relay socket of the fuse box, you have damaged the under side of the box, possibly melting some area resulting in issues therein. As suggested above, you might look around that area in the under side.
 
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Brando_TB

Original poster
Member
Oct 13, 2019
12
Albertville, AL
Hey guys, sorry For the very late response to this thread.
The issue has been fixed!
I took it to a mechanic who I know well, he couldn’t get around to it for a while so I had to wait a bit. He called me and told me that he used a device (of some sort) that helped him track down the shortage. He said the short was behind the instrument cluster, so he went ahead and unplugged the instrument cluster and once he did that, whatever device he was using was showing the short had gone away. He searched through all of the wiring in and around that area anyway and was about to chock it up as just being a bad instrument cluster, so he plugged it back up pending replacement and it just so happens that the short was completely gone then and Bertha started right up!
I’ve been driving her every day since with 0 issues. He charged me $150 for 2 whole days of trying to track down the short and for how long it sat in the lot. I didn’t care at all, I was just ecstatic that I could drive my trailblazer again.
Thank you to everyone who was helping me to try and figure out the issue, I learned a lot about my trailblazer and how to troubleshoot things.
My message to anyone who may ever have this problem is to try unplugging your instrument cluster and plugging it back up. I would’ve never thought to try it and really who knows why that fixed my issue, but it’s worth a shot for you especially if you where as desperate as I was.
 

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