Crank, no Start - U1000 and P0014

[Maverick6587]

I would normally do all of my troubleshooting first but, my vehicle is stuck at the store right now. So, I just want to make sure that I have all of the troubleshooting steps I need to run in order and I'm not missing anything big.

I was at the store last night and got into the 97x to start it and everything seemed fine. As I was backing out of the parking spot, I put it into drive and made it about 20 feet before the engine just stopped running. I coasted into another parking spot and continued to try to start it for about 5 minutes and it finally started again. I made it probably 100-200 ft. and the engine stopped running again.

I immediately assumed I was having the "Starts when cold and won't run when hot" issue. I kept trying to start it for about 15-20 minutes as I waited for my GF to arrive. No dice. I ran the scanner on it and it has the following Current and History codes.

Current Codes:
P0014 - Camshaft Position Sensor - Timing Over Advanced
U1000 - Class 2 Data Link Malfunction

The two below are active codes because I do not have my transfer case plugged in.
C0306 - Motor A/B Circuit Malfunction
C0327 - Encoder Circuit Malfunction


History Codes:
U1064 - Lost communication with Body Multiple Control System
U1160 - Lost Communication with Convenience Control System

I do have a Tech 2 but, I have only used it to replace a radio and run a case relearn. Am I correct in running a Class 2 Message Monitor check withing Diagnostic Circuit Check, to see which circuit is malfunctioning?

Checks I will be running tonight along with the Message Monitor Check.

1. Checking fuses
2. Looking at the wiring for the tailgate (Is it just the wires inside the rubber boot at the top of the tailgate or it is also the wiring inside the tailgate?)
3. Ignition Switch
a. There are two different types of ignition switch starters that I have found. Which one is the correct version,
- ACDelco D1426D GM Original Equipment Ignition Switch
- Standard Motor Products US-337L Ignition Starter Switch
b. This seems to be one of those parts that everyone just defaulted to "It's the same as a trailblazer." Maybe it
is? I think I'll just grab this from the junkyard to start with. They actually just got a 97x in the yard yesterday, so
hopefully I'm safe with that one.

Let me know if there's anything else I should be checking.

EDIT: I'll tow it home today if I have to. I just really didn't want to (if I don't have to) with my GF's 08' Escape.

 

[Mooseman]

I do have a Tech 2 but, I have only used it to replace a radio and run a case relearn. Am I correct in running a Class 2 Message Monitor check withing Diagnostic Circuit Check, to see which circuit is malfunctioning?

That would definitely be your starting point after checking what you have listed. If that proves to be inconclusive or nothing is responding, pull the databus main connector comb and jump the OBD port to each module while you ping the module in question. This video shows how to do that.

Definitely check the fuses and ignition switch first. Check the output of the switch.

The U1000 is a general code for when it's not running so I wouldn't worry about it too much. However, those historical U codes could be a clue. I would just erase everything just to get fresh codes because if it's an intermittent issue, it automatically goes to historical and some codes take a very long time to erase.

Edit: I'd stick with the ACDelco switch. That is the correct number. That Standard part number is wrong. Should be US331 according to RA.

 

[Maverick6587]

Thank you @Mooseman
For the wiring on/in the tailgate is it just the wires in that rubber boot that normally break/tare, or do I also need to take the tailgate panel off as well?

 

[Mooseman]

Not sure why you're looking at the tailgate except for a dead short on the databus line. A simple break wouldn't cause those symptoms and you would likely get a loss of communication to the LGM. I'd concentrate on the other stuff first.

 

[Maverick6587]

Repairing the liftgate wiring was a suggested "commom fix" from the Bluedriver app for the U1000.

Those parts I listed are not correct it's ACDELCO 15250556 for 97x the ignition switch. I cannot find that available anywhere online. It looks like I'm going to have to make a quick stop at the junkyard for sure.

@Mooseman Do you know if the "wood" panel on the center console can be removed by itself? My tools are in the 97x and it's far from the junkyard. Just trying to figure out a quick and easy (least amount of tools as possible) way to remove that ignition switch.

The lock cylinder and the ignition switch are sandwiching the panel. There's nothing else (other than the electrical clip) holding the ignition switch to the vehicle, right?

I might just take a little jigsaw with me and cut it out. I hate destroying other parts in the process, but I just don't have time. I get out at 3:30 and the junkyard closes at 4:30.

 

[Mooseman]

I believe it can be pried off. The tabs on mine are broken and had to use screws to hold it down. And IIRC, you need to remove the entire console to get to the switch.

I totally forgot it's a Saab. Yeah, that switch and cylinder are one piece so you'll need the key too. It's also held by a few small bolts. Total PITA. And you'll also need to do a VATS relearn since the key chip will be different. That Tech 2 will be useful but it will need security access, meaning you'll need Tis2000 running as well.

Maybe just check.yours first to confirm if it's working or not.

Edit: Did you check with the dealer? Just give the part number. It might be available.

 

[Maverick6587]

I was able to grab it yesterday. The saw definitely made that job 10 times faster. I did need a 10mm and a Philips head screwdriver. luckily there was a gentleman near me that was willing to share his tools. I totally forget to ask if they had the key to be able to depress that little metal piece to get the lock cylinder out. I'll check with them today when they open.

So, I ran every test I could find with the Tech 2 and everything was active and passed. I cleared the U1000 twice and it came back both times. I checked every fuse and all of them had continuity, EXCEPT the 125 amp fuse (screenshot below) at the end of the fuse block. The Class 2 Message Monitor read everything as active, nothing showed as inactive. There was an Unknown Device 7D Inactive listed at the bottom in one of the checks, but that only showed up once. Not sure what that was.

On the 125 amp I tested continuity in about 8 different ways on those 4 metal dots on the fuse itself. Should I have been able to read continuity between any of those 4 points? I did have continuity touching both of the posts that the fuse is connected to, but I assumed I would since they are connected to a battery positive in some other location?



I could not scan any trouble codes with the Tech 2 I was only able to get the DTCs with the bluedriver scanner, screenshot below of no communication with the Tech 2.

EDIT: I'm just going to swap that fuse out tonight. I've seen a few posts about that blowing and the vehicle not starting and the fuse is only $5. I don't understand why I just didn't unbolt the fuse to test it, it was late and I just wasn't thinking I guess.

As a side note, I forgot to mention that I lost amperage to my sound system right before the 97x stopped running. Maybe this blew and stopped giving power to the bose amp? I haven't checked the wiring diagram yet.

 

[Maverick6587]

The junkyard doesn't have the key for the 97x I pulled the ignition switch from. Just called a locksmith who said he can't pick that lock cylinder for me. So, now I'll just have to drill the cylinder to be able to turn the lock cylinder.

 

[Maverick6587]

I think I'm going to grab the BCM from that 97x today, just because that was a previous code for loss of communication. Does anyone know if I will need any tools to remove that?

It looks like it has the one wire connector I just can't see from any pictures online how it's connected to the rear fuse box.

 

[Mooseman]

That will also probably require some reprogramming for VATS to work. Again, before touching anything, check the output of the ignition switch. BTW, is the security light on?

If after you check all this and your ignition switch is really at fault and can't get that junker switch work, I have one here with a key.

 

[Maverick6587]

I swapped out the 125 amp fuse, which did not fix anything. I did, however, test both fuses 4 pins and none of them have continuity. So, they must just be in place compressing the plastic and smaller in diameter to not touch the metal they are going through. Anyway...

I didn't get much done last night as I was running late to get to the vehicle. I also removed the ignition switch and did not have time to test it or drill out the replacement ignition switch. I did try and unplug each of the Class 2 connector plugs, hoping that it would start. If it was in issue with the rear it would have started. If you, however, unplug the front plug, when you turn the key nothing happens.

I'm going to tow it to my parent's house tonight so I have the entire weekend to troubleshoot it in the barn. I didn't get a chance to test each of the Class 2 pins last night. I saw 16 active and fully functional modules on the Tech 2 running the Message Monitor.

Plans for further testing:

1. Check the output of the original ignition switch
2. Check each pin of the front and rear Class 2 connectors
a. verifying the power and ground of both the front and rear are good
3. Unhook the radio and Bose amp
a. Since I lost power to the Radio system a few days before it stopped starting I assume it might be related
4. Replace the ignition switch and/or the BCM
a. I grabbed the Candi module to be able to run the security reset for either module replacement and I finally got Windows XP and Windows 7 running in Virtualbox with TIS200 running on my laptop.

 

[Maverick6587]

This past weekend was just a mess... I didn't have much time to play with the 97x at all.

I did remove the radio and put the stock radio back in. The lower power I issued was fixed by doing that. I assume I blew the amp in the aftermarket head unit.

I swapped out the BCM and the security light did not turn on. It would only turn on if I swapped the ignition switch or the Ignition module that sits behind the ignition switch in the center console. I forgot to check the output of my original ignition switch and I could not figure out how to run the Tech 2 to do a security relearn. I did try the manual key in the On position for 10 min. on and 10 sec. off for a total of 30 min. and 30 seconds. That did not work. So, the security light is still on.

I ran the Class 2 Message Monitor again and here are the modules that show as active:
VID/EVO
DRR
BCM/BFC/DIM/SBM/TBC
ABS/TCS
ATC
PCM/VCM
SIR
IPC
RADIO
ONSTAR VS-3B
ACM/HCM
PDM/RDCM
LRD/LGM/EGM
MSM/SCM/DDS
RSA

When I started to power each individual pin on the connectors. I found that pin 8 (starting from the purple wire) turns on, I think it was 11 modules and the following go active and then inactive after 10 seconds:
DDM/LDCM
PDM/RDCM
LRD/LGM/EGM
MSM/SCM/DDS
ONSTAR VS-3B

I assume I am missing two modules. Initially, there were 16 modules that turned active. On my last scan only 15 displayed, those 15 are listed first above. Does anyone have the full list of modules that should show as active?

EDIT: I also unplugged the rear Class 2 comb to see if it would start with that unplugged hoping to narrow down which area had the bad module. It did not start. So, I assume the module is related to the front Class 2 module network?

I tried removing the rear, because in the video that mooseman posted he removed the rear comb and was able to start the vehicle. I was hoping I would have the same luck. I tried removing the front and starting it, but it doesn't even crank if you remove the front, which I assumed would happen, since the PCM and ignition switch would not be connected.

 

[TJBaker57]

There was an Unknown Device 7D Inactive listed at the bottom in one of the checks, but that only showed up once. Not sure what that was.

Don't know if this applies but there is this document at fastfieros that states address ranges for Physical adressing for various controllers. It might suggest that unknown 7D has to do with a lighting system controller? Never heard of such a controller.

VPW Communication Protocol

 

[Maverick6587]

@TJBaker57 Nice find!
I see that ID range, $70-$7F Lighting. The only thing I could find for the lighting controller/module was for the flasher, which is just a relay.

You know what though... My flasher is the quietest flasher I've ever heard. I have to look at the DIC to whether I left turned one of them on or not. Is that normal for the 97x?

I would gamble that replacement, but I only saw that unknown 7D the one time and that is a $50 part. I might grab one from the junkyard for testing though. I left the 97x at my parent's house, so I can't replace any parts until the weekend.

I ran a scan yesterday morning with Bluedriver and found this interesting. It has U1000 listed in Shared Address modules as well as Theft Deterrent Modules.

 

[Maverick6587]

I found the list of Class 2 modules from trailvoy. It looks like I'm missing the ECM from active modules on the network. So, ECM swap?

Intermittent Horn Operation

forums.trailvoy.com

Edit: NVM, that's for the 5.3.
Although, I don't see the Transfer Case Control Module listed. Should it be listed as TCCM in the Tech 2? NVM, I have that unplugged.

 

[Mooseman]

Yeah, the V8 have separate ECM and TCM whereas the 4.2 has one PCM doing both. Yours is showing the PCM so looks like it's alive.

I'd pull the front comb and jumper only those necessary to start the engine. PCM, BCM and the OBD port to monitor in case it's something interfering with the canbus.

I don't know why but I have a feeling it's not an issue with the canbus. You definitely have to test the ignition switch.

 

[Maverick6587]

I tested all of those on the front comb individually and they all went active. Since I have the TCCM unplugged could that be it?

On the ignition switch. I didn't test that because I wanted to test the big things I thought could be the issue. I figured since it cranks a signal is being sent from the ignition switch? Or is there a second signal that could not be reaching the PCM telling it to actually fire (spark/fuel), coming from the ignition switch?

The ignition switch I got from the junkyard was in fact junk. I took it apart before I was going to attach it and found a mess. mine looked clean with zero burn marks on it.

 

[Mooseman]

Alright so it cranks but won't fire. Did you check the basics? Air, fuel, spark? Fuel pump priming? Fuel pressure? Fuses and relays good? Tried starting fluid?

So if the PCM is sending a crank signal, it's happy with what it sees. If something down the road from it is missing like fuel or spark, it won't know that. Another possibility is the crankshaft sensor. The Tech 2 should be able to show the signal being received while cranking.

 

[budwich]

quick way to check things... since you have "crank", get a can of starter spray and spray some in the intake (or otherwise). If the thing at least "fires", then you have an electrical / fuel delivery issue associated there abouts. IF there is no fire, then you have an electrical / system issues (mechanical engine system).

 

[mrrsm]

FWIW... and considering that you perhaps more than most have "The Chops" to know/learn How To Use an Inexpensive Hand Held Meter-Oscilloscope, If you want to get a Graphed Square Wave look-see at what the 'back-probed' Pulled COMB Class 2 Network Connections look like or what the CKP Sensor and other Hall Sensors are doing on an EZ to Use Graph Sceen... Take a look at this LIUMY LM2001 Unit on Amazon for only $79.00. It has pretty much exactly all of the Basic Oscilloscope and DMM Diagnostic capabilities of what you need to know RIGHT NOW during this present dilemma. The Updated Version can handle up to 20 Amps:

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[Maverick6587]

Don't I feel less than intelligent right now. That U1000 had me thinking it was a computer issue stopping fuel/spark from happening. Since I did (I don't anymore) have that P0014 I guess it could be things like the camshaft sensor and/or the crankshaft sensor.

I"ll have my dad try some starting fluid today and see if she fires up or not. If the crank sensor is bad, would running a crank relearn harm anything?

I didn't hear anything when it stopped running or before it stopped. What are the chances or things I would hear if I broke the timing chain or the camshaft phaser or one of the other timing gears broke a tooth? I only ask because things like this are right up my alley of luck. I do have a spare car at the moment so, it would be perfect timing to have to replace that timing chain and everything that chain touches.

Honestly, It wouldn't surprise me if that fuel pump died on me. It is a Delphi pump and the way that it slowly died off that second time would point to slow fuel feed as the pump died and the engine took the remaining fuel/fuel pressure from the line. It wasn't an immediate stop of the engine.

@MRRSM I do have an oscilloscope but, I'm not even sure where I packed that during our house move two years ago. I'll try to find that today.
That is pretty amazing that someone built a DMM with an oscilloscope function built-in though and it's very tempting to buy just because it's so compact and cheap for an oscilloscope/DMM!

 

[Mooseman]

If the crank sensor is bad, would running a crank relearn harm anything?

You can't do the CASE relearn if it's not running so... Since you do have a Tech 2, it's easy to do the CASE relearn if the crank sensor happens to be the issue. It will run without the relearn since the error is only to let you know if the timing is off.

I didn't hear anything when it stopped running or before it stopped. What are the chances or things I would hear if I broke the timing chain or the camshaft phaser or one of the other timing gears broke a tooth?

Not very likely. The timing chain system in this engine is quite good and have only heard of a few failures. My chain tensioner failed and it still ran with the chain flopping around at idle. My phaser also failed but it still ran but poorly with codes. You could check with a compression test. I would think that it would sound weird while cranking the engine with cams not moving. P0014 is usually due to a bad CPAS.

My money is on the fuel pump, especially since it initially would run cold and die when warm.

 

[mrrsm]

All of the Timing Sprockets on the GM 4.2L Atlas Engine Design are made of High Grade, Drop Forged Steel and so the likelihood of any one tooth or series of them "snapping off' would be well nigh impossible. The Motor is in the Class called "Interference Engines" and so if the Engine "Jumped Timing"... You would NOT be able to turn the Rotating Assembly without having the Valves hitting the Tops of the Pistons, so that is also very unlikely.

As for Snapping the Timing Chain... while those Roller Links 'relax' considerably over time... the Steel they are made of is so strong that you could probably lift the front end off the ground with a Used One and it would not snap, so I would not consider that as a problem; other than the Timing getting so out Out of Whack from having such Worn Timing Chain Components and Tensioner that the Compression-Spark-Power Cycle could get so far off as NOT being able to fire at the proper BTDC on all (6) Cylinders.

As per @Mooseman 's recognition... The likelihood of having FUEL problem on the "Engine Firing Triad" seems very worthwhile looking into, and if you DO locate your Oscilloscope... (and if you have a Cheap HF Low Amperage Clamp) Consider what the VOP Eric "O" from South Main Auto suggests doing that will confirm or eliminate a Bad Pump with conviction...using Wave Form Analysis (Bad vs. Good) without having to Drop The Fuel Tank to find out. Take note of the "Give the Fuel Tank a SMACK on the Bottom" Technique using a Dead Blow Hammer to try and "Wake It Up" and see if the FP Primes and the Engine Starts... and Don't Forget to Wear Eye Protection from the Falling Sand , Dirt and Debris while you're Banging on the Kettle Drum under there:

Beware any 'Strange Wave Forms' present when Scope Diagnosing any Fuel Pumps that employ a Fuel Pump Duty Cycle Control Module as described here:

 

[budwich]

don't get too carried away with my "system issue / mechanical", its equally likely to be electrical... as you indicate, there are electrical things dealing with timing or "non-thereof". Once you determine whether it is or isn't fueling, you can go down the road on some more checks on the "no fire" IF that is the outcome.

On a side note, handheld "small display" scopes (single channel) are readily available for under $100 to do some "signal tracing" without connecting up to any compute power.

 

[mrrsm]

As per @budwich …This is a TRUE Tiny, Single Channel, HD Color Touch Screen Oscilloscope with Dual BNC Connectors that apparently works GOOD... for Under $60.00. All you would need to get then is a Low Amperage BNC Amp Clamp and be able to do a LOT of non-destructive, very rapid and reliable Automotive Wave Form Diagnostics:

JYETech DSO Coral Pocket Battery-Powered Oscilloscope w/Color Touch Display (DSO112A): Amazon.com: Industrial & Scientific

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This is a Funny, On Topic, Entertaining... AND Very Informative Video describing how this inexpensive device works:

...and HERE is a Technician working on a Class 2 "Dead Network" problem where he pulls the Under-Dash Plastic-Metal Comb on a 2003 Chevrolet Trailblazer and does essentially the same things that the Tech-Mechanic Mr. Robinson did in the Video provided by @Mooseman.

But in THIS case... The Tech-Mechanic is using an Inexpensive, Single Channel Oscilloscope similar to the < $60.00 DSO112A "Cheap-O-Scope" shown above and on Amazon to probe for the Pulse Width Modulated (PWM) Signals or their absence for each of the various Pin-Probed Modules:

 

[mrrsm]

Awww Hell...!!! @budwich convinced me to look once again... and THIS Hand-Held (2) Channel Unit that comes with ALL of the Great and Necessary, Dedicated Oscilloscope Performance Bells and Whistles was just TOO Damned Tempting to pass up (...and it will STILL work with Laptop Computer Software for Data Analysis and File Transfers). This is The BEST of Both Worlds for the Lowest Price vs. Highest Quality available for only $163.00 via Amazon with an Average (2) Day FREE Delivery Time:

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[Maverick6587]

Well.... I figured out the ol' crank - no start issue... Turns out that the fuel pump power connector (not the pressure sensor) was not snapped into place. I went to remove the power connector and it just pulled off with almost no force needed.

The "broken" fuel pump was a Delphi pump and I replaced it with a Bosch fuel pump. I didn't have time to test it by plugging it back in to see if it would run. That took care of the CEL but, I still have an active U1000 code though. I cleared all codes and ran it again and it still shows the U1000 as being active. I did, however, zip tie the Bosch fuel pump power connector in place though.

There were a lot of U1### codes after I replaced the fuel pump. I assume those were from my testing from this weekend on modules by unplugging them. Some of them do not make any sense though unless they were controlled by the Body Control Module. The HVAC, Convenience Control, and Engine Control system error codes do not make sense unless again, they are controlled by the BCM.


All of the U1000 codes that I cleared:
U1000 - Class 2 Data Link Malfunction
U1040 - Lost Communication with Brake/Traction Control System
(U1160 - Lost Communication with Convenience Control System
U1161 - "
U1162 - ")
U1016 - Lost Communication with Engine Control System
U1088 - Lost Communication with Restraints Control System
U1064 - Lost Communication with Body Mulitple Control System
U1152 - Lost Communication with HVAC Control System
U1166 - Lost Communication with Convenience Control System
B3055 - No Transponder modulation/no transponder - This one could be from me messing with the ignition switch?

Codes that still exist after all codes were cleared:
U1000
B3055 - No Transponder modulation/no transponder

EDIT: I forgot to mention that the ole' 9-7x runs like a champ again after the fuel pump replacement. I just need to trace down that U1000 error now.

@MRRSM I have that oscilloscope sitting in my Amazon cart right now. Just waiting for the refund for the original fuel pump.

$162 is not bad at all! I think I paid $300-$400 for my desktop oscilloscope. The portability and color screen is quite amazing.

 

[budwich]

Awww Hell...!!! @budwich convinced me to look once again... and THIS Hand-Held (2) Channel Unit that comes with ALL of the Great and Necessary, Dedicated Oscilloscope Performance Bells and Whistles was just TOO Damned Tempting to pass up (...and it will STILL work with Laptop Computer Software for Data Analysis and File Transfers). This is The BEST of Both Worlds for the Lowest Price vs. Highest Quality available for only $163.00 via Amazon with an Average (2) Day FREE Delivery Time:

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View attachment 91689View attachment 91690View attachment 91692View attachment 91693View attachment 91694View attachment 91695View attachment 91696

didn't mean to get you dragged down the "consumer hill"... I picked up a cheap single channel hand unit in the summer to use for other things (like troublehshooting electronics... ie. tv, receivers, etc) and was amazed at the cost versus value versus ease of use.

But alas, the OP found the "old use your eyes and hands" method solved the problem... c'est la vie... a good outcome is always good.

 

[mrrsm]

I'm glad you powered through the mysterious problem and found the solution. The only other observation I can make about the lingering UXXXXX Codes is to cast a very Skeptical Eye at the Three PCM Connectors for any misaligned "Green MetraPack" Weather Pack Seals; perhaps with dirty connections in the Pin Sets inside. The same suspicion may involve having a Sketchy PCM as well. Wherever the SPXXXX Grounds converge on the Truck Body... Remove the Comb(s) and re-plug them and ensure Good Ground contacts for them all. Using CRC Electrical Spray Solvent will help clean out anything that might be 'lingering' inside of them.

As much as I REALLY like my other Hantek (8) Channel Oscilloscope (vs. the over-priced $3,000.00 PICO flavor) with its high functionality and Flexible Tablet-Laptop Software capabilities... @budwich 's sensible observation about being able to "move around and under the vehicle" made perfect sense. With its recent arrival and unboxing, all of us should know that I have absolutely NO "Buyer's Remorse" about getting this Kool KKMOON Hand Held Scope. It is a very well appointed unit with a Clear Color Screen. Having the TWO Channel Scoping capability does make a difference when comparing several, related 'Voltage over Time' graphed issues, such as when testing EFIs.

This Video will give a Basic (Sort Of) Un-Boxing and a Run Down of its Features. Please note that contrary to what the VOP says about NOT having any "How To Use" Instructions that if you install the PDF for this Unit from the Included Mini-CD ... Many MORE Features beyond that small Pamphlet will be available for study.

With some Practice... the Unit features will become very intuitive. For the sake of Safety and Endurance, I recommend getting the NITECORE i4 LI-Ion Battery Charger and the 3400 mAh pair of Protected LI-Ion Batteries. The KKMOON Unit uses One and Stores the Other in an adjacent, internal slot. Normal run time is around 4-5 Hours between Charges:

 

[Maverick6587]

@MRRSM I am actually very skeptical of my PCM at the moment. As I didn't have time this weekend nor today to set that partition to run Linux as the OS for the Tech 2. That is the plan for tomorrow!

I'll try to reprogram the PCM and see what the result is for the ubiquitous U#### code. I'll pull a PCM from a trailblazer at my local u-pull-it if that doesn't change anything. At this point... It's the only thing I don't have a spare part for.