Ok, if you are telling us that when you have the troubles, the only way to get the key turned all the way off and pulled out is you need to use the override button on the ateering column then I will tell you to get at the ground point connection under the carpet on the front passenger side near the frontmof the console. This is ground G201 and a whole boatload of stuff depends on this ground. I spect and clean that up good.
No crank no start isn't it lovely
- Thread starter bennieRohde
- Start date
Ok, if you are telling us that when you have the troubles, the only way to get the key turned all the way off and pulled out is you need to use the override button on the ateering column then I will tell you to get at the ground point connection under the carpet on the front passenger side near the frontmof the console. This is ground G201 and a whole boatload of stuff depends on this ground. I spect and clean that up good.
Okay. I did a quick look over but I'll actually pull it apart and sand it down. I'm assuming I should disconnect the battery negative terminal?
By any chance have you removed the switch for inspection of the contacts? There are 5 different contact sets in there. Here is an example of worn contacts in these switches where the red circles are...
I have previously removed it, thinking it could be bad. And I pulled one from a working 2000 trailblazer and installed it and it had no issues. Both ways. I also had a friend pick me up a brand new one as well... Which I haven't plugged in. I could but was afraid of the security light. So I left the one in from the trailblazer. And the trailblazer still has the one from envoy in it.
Or it could have been the switch from the envoy in the junkyard. Was in a collision and I was there for other parts anyways so I grabbed it. So it could actually be that one too.
It should not affect the security system at all. If using an old switch it would be good to check the contacts. The covers on the switch come off reasonably easy with a small screwdriver. There are little tab locks that hold the covers on. There are three contacts on one side and two on the other side. Turning the gear makes the contacts open and close.
Okay I'll check that. I just cleaned that ground up. I sanded the paint on the body off. And cleaned the bolt holding it in and all contact points. No change as of yet. Can hear the BCM click when I try to turn it over. I'll pull the switch out and check it.
Okay so I took out old ignition switch. Remembered that the previous owner had actually bought a new one still in package in the garage. Went an got it. Put it in no change. Installed lined up correct. Feels right in key hole. Just the same situation
She bought that switch right before she talked to me about her intermittent no start. That's mine now. I had forgotten about it.
Also. Here's another thing I encountered. On the dash it does specifically have PRND321. However, I cannot manually shift the car into 1st gear. It's as if it doesn't exist when trying with the shifter. I looked into the transmission shift selector and found that it had a different part # than what was supposed to be on it by OEM part #. I need to find the old switch because I also replaced that. But I'm wondering if the transmission was changed in this car or something because the switch I took off was from 2014 it had a date on it. The car is a 2002. And has 262k on the dash. I never cross referenced that old switch to see what it belongs too. But the car has drove and shifts fine with the one installed. Just no 1st. Previous owner said she's never tried to put it into 1st gear manually either.
Here are a few more thoughts to investigate:
(1) Open the Fuse Box and take a Screw Driver (EDIT: 7mm Socket) to the 3 Galvanized Steel Fasteners holding the Upper Fuse Block *caddy* to the Under - Side Harness Blocks. Sometimes if those are loose...the Thick, Copper Tracing Wires will lose contact with the Fusing Blocks just above them. Alternatively...Loosen the Fasteners, Pull the Fuse Block Harness Plastic Segments loose... and Spray them all out from Top to Bottom with CRC Electrical Contact Solvent, then Plug Them Back In Nice & Snug & Re-Tighten:
(2) Take a Bright Flashlight and after Masking up with an N-95 Face Mask and wear Good Eye Protection and a Pair of M11 Nitrile Gloves. Now Go On The Hunt under the Hood and look over ALL of the Harnessing for ANY Signs of Chewed, Gnawed Wire and Connector Damage from Rats or Field Mice wearing down incessantly growing Teeth. (The North American Deer Mouse is the Biggest Culprit).
(3) Look for signs of Headliner Damage and Nesting under the Air Box and in the corners of the Engine Compartment such as Piles of Pine Needles and Fur, etc. The Health Threat in such cases is NOT Trivial (The HANTA Virus can be contracted through the inhalation of Feces and Urine Laden Dust or easily transferred to the mouth and eyes and THIS Disease Kills 40% of those unfortunate enough to become infected:
(4) You are at an advantage with having the Fuel Filter located along the Driver's Side Body Rail, just aft of the Front Door. You should consider doing the R&R of the Old Filter and while you are at it, DRAIN THE FUEL TANK of any Water into a Bucket to investigate its condition (or perhaps sabotage liquids) being poured into the Fuel Tank and interfering with the Start and Run Engine conditions. The Missing Fuel Cap makes this effort even more critical, since the taking or discarding of the cap might indicate other issues with the Prior Owner and other parties.
Note: Some of the Credit for these Rodent Infestation images goes to @christo829
(1) Open the Fuse Box and take a Screw Driver (EDIT: 7mm Socket) to the 3 Galvanized Steel Fasteners holding the Upper Fuse Block *caddy* to the Under - Side Harness Blocks. Sometimes if those are loose...the Thick, Copper Tracing Wires will lose contact with the Fusing Blocks just above them. Alternatively...Loosen the Fasteners, Pull the Fuse Block Harness Plastic Segments loose... and Spray them all out from Top to Bottom with CRC Electrical Contact Solvent, then Plug Them Back In Nice & Snug & Re-Tighten:
(2) Take a Bright Flashlight and after Masking up with an N-95 Face Mask and wear Good Eye Protection and a Pair of M11 Nitrile Gloves. Now Go On The Hunt under the Hood and look over ALL of the Harnessing for ANY Signs of Chewed, Gnawed Wire and Connector Damage from Rats or Field Mice wearing down incessantly growing Teeth. (The North American Deer Mouse is the Biggest Culprit).
(3) Look for signs of Headliner Damage and Nesting under the Air Box and in the corners of the Engine Compartment such as Piles of Pine Needles and Fur, etc. The Health Threat in such cases is NOT Trivial (The HANTA Virus can be contracted through the inhalation of Feces and Urine Laden Dust or easily transferred to the mouth and eyes and THIS Disease Kills 40% of those unfortunate enough to become infected:
(4) You are at an advantage with having the Fuel Filter located along the Driver's Side Body Rail, just aft of the Front Door. You should consider doing the R&R of the Old Filter and while you are at it, DRAIN THE FUEL TANK of any Water into a Bucket to investigate its condition (or perhaps sabotage liquids) being poured into the Fuel Tank and interfering with the Start and Run Engine conditions. The Missing Fuel Cap makes this effort even more critical, since the taking or discarding of the cap might indicate other issues with the Prior Owner and other parties.
Note: Some of the Credit for these Rodent Infestation images goes to @christo829
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Also I did take the entire fuse box out prior. Looking for messed up connections and such and didnt find anything. I did have a friend who's also a mechanic with me who was helping me test probe everything and check wire diagrams for the PCM to ignition and BCM and all that and we couldn't find an issue there at the time. This was a couple weeks ago now.
By the way... There are Three Conditions which must be met in order to be able to Start the Vehicle and then ...Move The Shifter:
(1) The Condition of the Battery Voltage is CRITICAL for the GMT360s to function properly. So in some instances where the Battery is either NOT up to Par or literally in a "Run Down" Condition... the Solenoid will NOT have enough Energy to activate...and inform the PCM-BCM that conditions are Nominal. Anything above 12.5 or so Volts DC should do the trick.
(2) It is always necessary for an Occupant of the Driver's Seat to Press down on the Brake Pedal, thereby activating a Solenoid holding a Locking Pin in place restricting the ability to move the Shift condition of the "T" Handle Cable Control Mechanism of the PRNDL... to slide the 4L60E into Gear after accidentally Starting the Engine. This is a Safety Mechanism as a preventative against either The Youthful, The Foolish or The Careless from Accidentally Starting the Vehicle and sending it down the roadway in any uncontrolled manner.
(3) The PRNDL Park Neutral Safety Switch mounted and surrounding the 4L60E Shifter Pawl MUST be adjusted ... Just Right... so that the Position of the Dashboard Lighted PRNDL Indicator when NOT either in PARK or NEUTRAL... Prevents the Engine from Starting while the Transmission is Physically "In Gear". The Proper Setting of the Shifter Pawl on the Transmission Base demands this method to confirm their positional reconciliation. There are Two Small Bolts holding the adjustment in place with only about 5 Degrees of left or right rotation about the Axis of the Pawl Rod. This delicate setting may take a few tries before getting things into agreement...and then lightly snugging down those two Bolts.
(4) Mind that you are aware of the fact that the Two Electrical Connectors may have both a Length of String tied in between while Hot Glue was being applied to the Two Inner Ports of that Switch and their Harness Connectors. Thus, the use of a Hot Air Gun will become necessary to loosen them up if replacing that switch becomes an issue. Investigate the Wiring and Connectors thereon as well for any cut, chewed or damaged wiring harnesses.
(1) The Condition of the Battery Voltage is CRITICAL for the GMT360s to function properly. So in some instances where the Battery is either NOT up to Par or literally in a "Run Down" Condition... the Solenoid will NOT have enough Energy to activate...and inform the PCM-BCM that conditions are Nominal. Anything above 12.5 or so Volts DC should do the trick.
(2) It is always necessary for an Occupant of the Driver's Seat to Press down on the Brake Pedal, thereby activating a Solenoid holding a Locking Pin in place restricting the ability to move the Shift condition of the "T" Handle Cable Control Mechanism of the PRNDL... to slide the 4L60E into Gear after accidentally Starting the Engine. This is a Safety Mechanism as a preventative against either The Youthful, The Foolish or The Careless from Accidentally Starting the Vehicle and sending it down the roadway in any uncontrolled manner.
(3) The PRNDL Park Neutral Safety Switch mounted and surrounding the 4L60E Shifter Pawl MUST be adjusted ... Just Right... so that the Position of the Dashboard Lighted PRNDL Indicator when NOT either in PARK or NEUTRAL... Prevents the Engine from Starting while the Transmission is Physically "In Gear". The Proper Setting of the Shifter Pawl on the Transmission Base demands this method to confirm their positional reconciliation. There are Two Small Bolts holding the adjustment in place with only about 5 Degrees of left or right rotation about the Axis of the Pawl Rod. This delicate setting may take a few tries before getting things into agreement...and then lightly snugging down those two Bolts.
(4) Mind that you are aware of the fact that the Two Electrical Connectors may have both a Length of String tied in between while Hot Glue was being applied to the Two Inner Ports of that Switch and their Harness Connectors. Thus, the use of a Hot Air Gun will become necessary to loosen them up if replacing that switch becomes an issue. Investigate the Wiring and Connectors thereon as well for any cut, chewed or damaged wiring harnesses.
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I had a similar problem on my 2002 Envoy. After confirming I was getting power to my starter solenoid, I thought maybe the solenoid was just stuck. Sure enough, took a leather mallet, tapped on the solenoid and starter a few times and it started right up. I keep the leather mallet in the car now. So far so good.
Hey Mrrsm yea. I noticed the hot glue issue immediately when I replaced that switch previously. And that's exactly what I did. Well sorta, I used a hair dryer as my heat guns settings are trash and it only has melt your face off mode. I managed to get it off and put a new one on. Didn't notice any damage to the plug connection or anything. No wire damage to/from it. I'm at work currently but like I said I'll be going and digging through the car for any rodent damage or corrosion too. And see about finding every single one of those main grounds in the front by fuse block. I believe I had found and cleaned 3. Also the starter ground and solenoid.
these ghost like problems sound so familar, I have a 2009 GMC Z71 and I call it the GM curse, for me, grounding has been the fix, one under the driver's door connected to the frame and those on the fire wall but the battery connection to the motor block needs special attention, I had to remove the block ground stud and clean real good with a wire brush wheel and a drill, with a set of booster cables try connecting Battery NEG to another spot on the block, also monitor the battery voltage to see what it does when you try to start. I have had to clean the motor stud several times over the years. I hope this might help you.
Okay so far I can't find any type of rodent damage or specific corrosion around the fuse box or into the firewall. No nests, nothing like that. This car has also never actually sat longer than maybe a month in the last 6-7 years. The previous owner owned it that long. And I've known also known her since right after she got it. She DID buy it from a used car dealer.
On another note. I did find that main ground from battery to motor and it doesn't look the best. Same with the ground under the driver door, which honestly I didn't know was there. So I'm going to clean those up and then post progress
On another note. I did find that main ground from battery to motor and it doesn't look the best. Same with the ground under the driver door, which honestly I didn't know was there. So I'm going to clean those up and then post progress
Okay i had to switch to my PC from mobile cause for whatever reason now when i try to comment the screen goes black on the website.
So, i cleaned those grounds up. also saw forementioned the fuse box holder screw things. they were 7mm bolts. they all were loose. so i tightened those down. the car started. when it was running no check engine or warning lights were on. just my oil light which i know its due, she said she hasnt changed it in a while. too long. i get paid the 31st so ill be doing that. ive literally recently gotten this car from the lady, she gave up on it and bought something new and just literally signed it over to me.
So, i cleaned those grounds up. also saw forementioned the fuse box holder screw things. they were 7mm bolts. they all were loose. so i tightened those down. the car started. when it was running no check engine or warning lights were on. just my oil light which i know its due, she said she hasnt changed it in a while. too long. i get paid the 31st so ill be doing that. ive literally recently gotten this car from the lady, she gave up on it and bought something new and just literally signed it over to me.
now outside of all of this, it has been an INTERMITTENT issue .... ridiculous. uhm, cant say for sure what did or didnt fix it. can say that those fuse block bolts as were explained have copper connections inside that need to meet for correct passage of power? so those being rather loose could definitely be an issue for sure. if it starts tomorrow morning ill be driving it to work and hoping it also starts on my way home or ill be on here asking more questions haha
I've gone out and started it a few times. No problems so far. It does have a service engine soon light though. Don't remember that one being constant. Everything is in working order though so far. Going to drive it to pick up my woman. I've been using her car and she is getting a ride to work for now.
Doesn't have anything to do with my issues with not starting I believe.... Anyways. I didn't have any issues this time. Car shifted gears and my blower motor worked. It Didn't last drive to recap.
Stopped at the store and turned it off and it started back up fine.
Stopped at the store and turned it off and it started back up fine.
Previously when this happened and I had gotten it started I drove it to and from work for about 8-9 days. So I'll keep this post updated with any changes.
You have probably already dropped in on THIS Dedicated "Grounds" Thread courtesy @Realism... but if not... Check this one out as a "Worthy Technical Read" ...especially for anyone living in the "Rust Belt" or whomever spies ANY Ground or Bonding Straps that are GREEN:
gmtnation.com
Electrical Ground locations
While troubleshooting a bad ground I came across some scans of the service manual regarding electrical ground locations for our platform posted on another site. This includes both short and long wheel base, as well as both 4.2L and 5.3L. Credit goes to Wex...
gmtnation.com
Mooseman
Moderator
I have a feeling it was something with the ignition switch. Since you played around/swapped it, it seems to have resolved the issue. Let's see what happens.
And yes, that code is not related.
And yes, that code is not related.
Yea it's definitely possible. We shall see. I checked out that thread about all those grounds. I've gone over maybe half or so of those. So I'll see about cleaning the rest of them up as well over the next few days. And I have some of that electric cleaner. Ive used it to clean other parts prior. So I might take that fuse box out too as you explained and spray it down too. Doesn't hurt.
Soo. I actually fought with it shortly again today. But ya know.. idk it takes time I guess. To go through every single thing... anyways it started earlier today. Went to the parts store for my other car ehehe. For some tool specific stuff. It did fine. Just went out to start it before sleep to see. Nothin. Same issue. Went hmmmm... Went to the BCM in the back to find those same bolts that were on the fuse box that I tightened. And sure enough they are. And they are loose too. I tightened them and the car lit up and bam, started. Combination of ground cleaning and connections being made? Idk ... Maybe those bolts were the culprits.
Will keep updated. What continues to bother me has been the intermittence of it. But this was a very short time from no start to start. When generally takes a lot longer. And it has acted like a ground issue or connection not being made or the like of. As we have also pondered on security issue but no security light has happened in a while. Weeks. Also I did mess with the switch a little I think when I put it in the cylinder either rotated or the switch mechanism did, because in the full start like cranking it over it felt like it didn't have as much turn/engage as prior. I did mess with that switch before going to the BCM and tightening bolts. And tried to start it in between, directly after/during the switch fixing. It does feel good now. It is also the new switch.
After/during this I'd like to talk to someone about a 2000 blazer / trailblazer 4.3 lol. My roommates. I must make another thread yes? XD have some general questions really. I do like to work on vehicles and do my best to learn. Been at it since I owned my first car, always tried to work on my own stuff. Been hard to find people who also have answers to things that are hard to find on the interwebs sometimes. And I can't afford full service manuals for everything, though I got a few.
Speaking of "Intermittent" possibilities... For around $20.00 ...after taking off the Air Box... shining THIS type of Inexpensive Laser Thermometer at the Tops of the Coil Over Plugs might reveal One or More that are OVERHEATING due to either having an Internal Short ...or excessively LEAN Combustion Conditions (Persistent P0300s) that can stress the Secondary Sides of the Coils enough to cause the Heat Radiators 'ATOP the COPS' ...to get HOT enough to BOIL WATER... or... BURN FINGERS... And...Cause the Engine to Suddenly SHUT OFF:
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Mooseman
Moderator
Yes, definitely in the other GMT section.
We do have them for the GMT360 and the full size trucks. Check my signature for links.
Re: Post #s 68 & 69... THESE Threads are some of quite a few priors like them that deals with the Investigation and Solutions for the P0420 Trouble Code problem:
gmtnation.com
gmtnation.com
And the Highlight Screen Print just below comes from "The Roadie" in this last Thread suggesting and emphasizing the idea of using a Simple Technique for determining whether or not the Ceramic (Precious Metal Rare Earth) Impregnated Cores have FRACTURED... by first laying out a Large Section of Clean Cardboard along the deck adjacent the CAT, right underneath the Passenger Side of the SUV.
Then... While using a Dead Blow Hammer to "Tap-Tap-Tap" VERY lightly along the bottom areas of the Stainless Steel CAT Container... If you hear anything that sounds like it rebounds similar to that of "Something Like...Keys and Coins being Dropped inside of a Ceramic Bowl"...THAT sound reporting back would confirm that the Cores have Broken apart and dropped down inside of the CAT Can. An R&R with an OEM Quality CAT would necessarily follow on:
Code P0420
Had my manifold replaced, basically P0420 came up with very poor/no response from throttle at stop to go. Today I found a loose nut at the stud connecting the exhaust pipe to the manifold. Seemed to be an easy fix, just tighten a nut? Did a test run nailed the gas from a dead start now able to...
gmtnation.com
SES Light P0420 - Need help diagnosing / replacement
Had this code come up today. I have 185K miles on the truck and never replaced the O2 sensor(s) or CAT. How should I go about diagnosing the issue? I saw Chickenhawk's post about checking the pressure (I would have to buy a pressure gauge, no big deal). I feel like it does struggle a bit on...
gmtnation.com
And the Highlight Screen Print just below comes from "The Roadie" in this last Thread suggesting and emphasizing the idea of using a Simple Technique for determining whether or not the Ceramic (Precious Metal Rare Earth) Impregnated Cores have FRACTURED... by first laying out a Large Section of Clean Cardboard along the deck adjacent the CAT, right underneath the Passenger Side of the SUV.
Then... While using a Dead Blow Hammer to "Tap-Tap-Tap" VERY lightly along the bottom areas of the Stainless Steel CAT Container... If you hear anything that sounds like it rebounds similar to that of "Something Like...Keys and Coins being Dropped inside of a Ceramic Bowl"...THAT sound reporting back would confirm that the Cores have Broken apart and dropped down inside of the CAT Can. An R&R with an OEM Quality CAT would necessarily follow on:
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So it's been like 2 weeks. No problems have arose yet. I have had the alarm randomly go off now and the key fob not work to disarm it. It does unlock and makes the noise, the fob works. But I have to turn the key over in the ignition to stop the alarm. Oddly seems to happen when I open the driver door. I haven't been engaging the alarm, I don't think it's auto setting it's self. But I am unsure.
Regardless, my main need was met and hasn't had an issue thanks for the help guys !
Regardless, my main need was met and hasn't had an issue thanks for the help guys !