2002 Buick Century 3.1 Cranks.. and starts momentarily. BCM code question.

Part1: www.scannerdanner.com/forum/post-your-re...-no-start.html#91994
Back at this pia.. I finally got the missing spark located and sorted out and it fired right up and it will run for 30sec or so before shutting off.
So now it'll throw a code or two.
Current:
PCM codes: p0102. MAF (was disconnected for ECU access)
p1626 BCM theft deterrent 
u1064 loss of a class 2 module communication.

The one that comes back after clearing them that has me totally confused is B1477 a missing RAP (or Retained power) relay communication.

I had to look for a while before finding it hiding behind the glove box and that's when I got lost.
The data shows it's location but that location is empty... An empty slot on the metal relay mounting bracket but no wiring harness, connector or relay to be found.
I have ordered a new one and an Rlink J2534 to program it with but don't really want to open either package if I can find a way to prove it's not* the BCM wanting to talk with a relay that's not even present on the car.
Any suggestions would be helpful.. hopefully.

The p1626 refers to the fuel enable status for the theft deterrent system.
Like Tyler suggested in your previous repair question topic, it would be wise to watch to fuel enable and theft status PIDs during the stall.

B1477 refers to RAP or Retained Accessory Power. This is when you turn the ignition off after a drive and can continue to use the radio and power windows before you exit the vehicle.
Most likely not related to the issue at hand.

Thanks for the reply, in looking up info on VTD system I saw a theft deterrent reset option and it went nowhere fast. (See pic)
The security telltale remains long after 10 minutes so the next step seems unable to process further.
 
Pids.

VTD during key start showed Yes to the PCMVCM in VTD fail enable ' pid
and Inactive for the fuel disable and automatic learn timer pids.



The Class 2 DTC check shows dtc's present in all the modules connections except
PCM/BCM
BCM/BFC/DIM/SBM/TBC
IPC
ABS/TCS
and the supplimental inflatable restraints.

The IPCluster shows a U1064 loss of comms with BCM/DIM/SBM
The Chassis has lost comms with the PCM and reports the class 2 malfunction 

It sure seems the BCM is the common denominator to me but I'd love to be wrong about it. Any more suggestions?
 

Find attached the location and power distribution diagram for the RAP relay.
 
 
As you can see, the diagram shows that, if equipped, the RAP relay is power for the sunroof and windows. 
Also find attached the Passkey relearn procedure as outlined by General Motors in service information.
 
Google or whatever AI isn't exactly the most reliable source of information. There a few variations of the relearn procedure and they must be followed exactly as outlined or will fail. I know from experience that 10 minutes means EXACTLY 10 minutes. If you let it sit 10min and 10sec, you need to start the process over. If you accidentally turn the ignition to the Crank position instead of the On position, you need to start over. 
Some of them want the ignition turned to Crank initially and some of them want the ignition turned to On initially. If this step is not followed correctly, you need to start over.
It's very easy for this "30 minute relearn" to run well over an hour.

The security telltale remains long after 10 minutes 

This alone seems to indicate an issue with the security system. As I I recall, the indicator should illuminate momentarily for the bulb prove and then go out.

VTD during key start showed Yes to the PCMVCM in VTD fail enable ' pid

and Inactive for the fuel disable and automatic learn timer pids

Do these PIDs change when the vehicle stalls after 30 seconds of running? Can the vehicle be restarted after it stalls without turning the ignition switch to the Off position?

Noah wrote:

Find attached the location and power distribution diagram for the RAP relay.
 

 

As you can see, the diagram shows that, if equipped, the RAP relay is power for the sunroof and windows. 
Also find attached the Passkey relearn procedure as outlined by General Motors in service information.
 

Google or whatever AI isn't exactly the most reliable source of information. There a few variations of the relearn procedure and they must be followed exactly as outlined or will fail. I know from experience that 10 minutes means EXACTLY 10 minutes. If you let it sit 10min and 10sec, you need to start the process over. If you accidentally turn the ignition to the Crank position instead of the On position, you need to start over. 
Some of them want the ignition turned to Crank initially and some of them want the ignition turned to On initially. If this step is not followed correctly, you need to start over.
It's very easy for this "30 minute relearn" to run well over an hour.

The security telltale remains long after 10 minutes 

This alone seems to indicate an issue with the security system. As I I recall, the indicator should illuminate momentarily for the bulb prove and then go out.
Yes it should go out but it stays on so do I wait for it to go out or turn the key off at 10min regardless? also fwiw service engine light is on.

VTD during key start showed Yes to the PCMVCM in VTD fail enable ' pid

and Inactive for the fuel disable and automatic learn timer pids

Do these PIDs change when the vehicle stalls after 30 seconds of running? Can the vehicle be restarted after it stalls without turning the ignition switch to the Off position?
I can't say if it does since it won't consistently start and run for that long. I believe those are the same ones I have seen from the beginning of my looking at them.
I have no idea what/why makes it run when it does. Or why the codes come and go..
I understand the RAP isn't that important but the why* it's being coded still confuses me.

FYI the Key is good   I checked it's resistance 

 

I can't say if it does since it won't consistently start and run for that long. I believe those are the same ones I have seen from the beginning of my looking at them.

I have no idea what/why makes it run when it does. Or why the codes come and go.

Ok, this is important information. So, just to clearly outline the symptoms, it does NOT start and run and then die after 30 seconds as you stated at the beginning and in the title of this topic?
 I apologize that I'm having a hard time following, but at the end of your last topic,
scannerdanner.com/forum/post-your-repair...cranks-no-start.html
it sounded like you discovered the firing order was incorrect while reassembling the intake manifold, put the plug wires on correctly, and the car fired right up.
Now it sounds like you're still experiencing the exact same symptoms as before when the firing order was incorrect, or are these new symptoms?
Again, I apologize for not being able to follow. Helping people on the Internet can be challenging. We can only use the information you provide and have to trust that the tests suggested are performed by you the same way they would be performed by anyone else, which is not always the case.

-IF the car consistently starts, and then stalls, this is typical of an anti theft issue on that generation GM.

-IF when the car starts and stalls, it then sets B1626, this reinforces the idea that there is an issue with the theft deterrent system. This idea is further reinforced by the report that the theft system indicator lamp never goes out.

If I am interpreting the symptoms and course of events correctly, then I would say that you should perform the VTD key relearn exactly as outlined by service information.
To answer your question about this test: I would turn the ignition off after exactly 10 minutes had elapsed if the indicator went out or did not. 
Typically, it will go out after 10 minutes if the process has been properly initiated. There have been instances when I have done this procedure and the light did not go out after 10 minutes. I find it best to continue on as instructed.

 

Noah wrote:

I can't say if it does since it won't consistently start and run for that long. I believe those are the same ones I have seen from the beginning of my looking at them.

I have no idea what/why makes it run when it does. Or why the codes come and go.

Ok, this is important information. So, just to clearly outline the symptoms, it does not always start and run and then die after 30 seconds? Correct 
 I apologize that I'm having a hard time following, but at the end of your last topic,
scannerdanner.com/forum/post-your-repair...cranks-no-start.html
it sounded like you discovered the firing order was incorrect while reassembling the intake manifold, put the plug wires on correctly, and the car fired right up. Again correct.

Now it sounds like you're still experiencing the exact same symptoms as before when the firing order was incorrect, or are these new symptoms? It would seem both, it turns over (smoother than before) but the same no fire. I haven't rechecked the CamSignal presence 

Again, I apologize for not being able to follow. Helping people on the Internet can be challenging. We can only use the information you provide and have to trust that the tests suggested are performed by you the same way they would be performed by anyone else, which is not always the case. There lies the rub..

-IF the car consistently starts, and then stalls, this is typical of an anti theft issue on that generation GM.
It only did that a few times 

-IF when the car starts and stalls, it then sets B1626, this reinforces the idea that there is an issue with the theft deterrent system. This idea is further reinforced by the report that the theft system indicator lamp never goes out.

If I am interpreting the symptoms and course of events correctly, then I would say that you should perform the VTD key relearn exactly as outlined by service information.
To answer your question about this test: I would turn the ignition off after exactly 10 minutes had elapsed if the indicator went out or did not. 
Typically, it will go out after 10 minutes if the process has been properly initiated. There have been instances when I have done this procedure and the light did not go out after 10 minutes. I find it best to continue on as instructed.

Will do (as instructed) and report back.

In the meantime I checked the BCM connectors with just my multimeter and watched for evidence of signal or voltage. Nothing abnormal found but I did see that Connector C3 A10  lists 2 options for RAP relay.. one without.
Then checked the P0106 and discovered a broken power supply wire which I repaired. I believe the 4pm screen shot shows its happy now. 

 

 

 

I need to up my reading the instructions game I think..
The test I was trying to do needed a little more than I thought.. it looks like I still need to get the Tech2 set up on my old laptop. Is a J2534 device the second tool required to perform the task?
From AllDataDIY..

TOOLS REQUIRED
 -  Tech 2
 -  Techline terminal with current SPS (Service Programming System) software
 1. Connect the Tech 2 to the vehicle.
 2. Select "Request Information" under "Service Programming".
 3. Disconnect the Tech 2 from the vehicle and connect it to a Techline terminal.
 4. On the Techline terminal, select 'Theft Module Re-Learn" under "Service Programming".
 5. Disconnect the Tech 2 from the Techline terminal and connect it to the vehicle.
 6. Turn ON the ignition, with the engine OFF.
 7. Select "VTD Re-Learn" under "Service Programming".
 8. Attempt to start the engine, then release the key to ON (vehicle will not start).
 9. Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF (the vehicle is now ready to
relearn the password on the next ignition switch transition from OFF to CRANK).
10. Turn OFF the ignition, and wait 5 seconds.
11. Start the engine (the vehicle has now learned the password).
12. With the Tech 2 (scan tool), clear any DTCs.

That method is faster, but it is not necessary. The 3x 10 minutes relearn is an alternative to the factory scan tool method.
I think at this point buying a J box and service information subscription may be an unnecessary expense, but that's completely up to you.

Should there be spark during the cranking portion of the relearn cycle?
When it says "will not start" is the PCM cutting the signal to the ICM preventing the firing of the plug?
I checked during one of the relearn start cycles and there was none.

To my knowledge, the VTD will not cut spark. Knowing there is no spark is good information!
If the car is missing spark, then there is likely another issue preventing the car from starting.

After taking with y cousin who went through GM training last night who wanted me to do the VAT resistor bypass I checked the ohms at the BMC connector with it unplugged from the BCM to see if there was any issues with the ignition key or cylinder but it read true and held steady in each position from key on through start.
Not gonna do needless 'repairs'
Now on to the lost spark..

Is there any thing that you recall having done when the car did have spark? Like maybe moving a particular connector or section of wire harness?
It's been a long time since I've worked on one these, have you seen this Scanner Danner video explaining the GM bypass ignition system?
Check out this video from this search, gm bypass ignition system share.google/U986FU5SMLGCvdSuz

After my cousin suggested that and I checked the BCM ohms readings one of the first vids to show up on my YouTube recommendations was one of your VAT resistor replacement vids for a 98 buick. Still not convinced I need to go there to fix my issues with spark.
Fuses and relays haxe been my focus when not installing replacement garage doors and stuff, and I did find a circuit to investigate,
The IP panel fuse for Crank, BCM ,Cluster and the one for the Heated mirror have no voltage going to in from the under hood fuse box 30A Ignition main fuse which is good and powered up.
So that seems like the best place to look.
Again..any insight is appreciated.
Thanks.

If that fuse does not have power key on, or in the start position, but the 30A fuse under the hood does have power, then you should investigate the circuit from the ignition switch, or the ignition switch itself.
Tell me if I'm looking at the correct fuse on the diagram.
 

With 5 different BCM fuses in the IP panel it gets a bit confusing but that is the one. I was setting up to look at the one with the dark green wire your yellow line crossed over but yes.. that's where I am at.

To busy to do much but did get this..
Fuse out and scope was hooked to leads from the fuse box terminals,
IP panel fuse A_3 & 4 (Crank signal, BCM, Cluster) channel A = 3 and B = 4 you can see the KI + KO prior to Start event (2x) so why is the supply from H (your line) is missing in the run position or does it stay on if the A_4 side of the fuse send a signal through the CAN bus?


 



Any particular events or tests you would like to see let me know.
Thanks again 

 IP panel fuse A_3 & 4 (Crank signal, BCM, Cluster) channel A = 3 and B = 4 you can see the KI + KO prior to Start event (2x) so why is the supply from H (your line) is missing in the run position or does it stay on if the A_4 side of the fuse send a signal through the CAN bus?

I don't see in the diagram what you are referring to? There will be no CAN bus signal transmissions through these fuses, this is strictly power distribution.
If there is no power at the yellow wire that is labeled H in the diagram at the interior fuse panel with the ignition switch in the start or run position, then you must check for power on the yellow wire labeled D1 at the ignition switch with key in the on position, and with the key in the start position.
Missing the power here with the key in the on position and in the start position only would indicate an issue with the ignition switch (assuming the power feed to the ignition switch on the red wire is intact.)

I ran tests on the key switch circuits between the IP panel and the harnesses 8745 and  85929 feeding up into the column.
8745 comprised of 8 and 10 gauge wire leading me to think those are the power supply from the battery etc.  I found all but the Dark green wires in that bundle.
There were 2 drkgrn in 85929 one 12gauge the other 14. My screenshot is the 12g one.
I'm  also running the AD diagnostic test for the ICM communication with the ECU rechecking all the connections are in the right order etc.. looking for the missing spark. But the fuse seems like the priority problem to me.
From what I can tell I think the next step is trying to run a trace from the IP panel fuse terminal back to the column and see what I can find out.
(Photo label describes the test in detail.)
Under col = tested harness there... Otherwise @ the IP panel terminals.

Sheesh... PDFs fouled that up huh?
Live and learn..