Truck wont start. PassLock Security issues

[enosez]

Ill try to keep this brief.

2003 Silverado 2500HD 8.1L Crew Cab

Just bought truck about a month ago. Truck was running/driving fine until about two weeks ago.

Went to start truck and it would sputter and die. Tried again and it would try and run and then die. (acted like it would run out of gas)

Let truck sit overnight and everything was fine the next day. (Because the situation was new to me, I did not pay attention to security light)

I did find it odd that the plastic on the column was only half on, so i assume the previous owner had some sort of problem here.

Fast forward to yesterday. I was working on why the passenger seat (motorized) was not working. I checked the fuses and stupid me decided to pull each fuse and check it and put it back in.

Truck started and ran and was able to park in the street.

When i went out to run an errand later the truck experienced the same condition. Would not start. So now I pay attention to security light. It blinks and goes out. Truck still wont start. Check the web and I see I may need to relearn the pass key.

Tried and it didnt work. Tried the 10 minute procedure numerous times.Now the truck would only crank. It did not start. Before it was like it ran out of gas. 

So I try the bypass by connecting the yellow and black wire that are on the ignition key and try the re-learn process. NOTHING.

Now the light just stays on constant.

So I check with a scan tool and found P1631 and B2948. Now the scanner can clear these codes but we did not clear them until I checked here.

 

So I came here looking for some advise and help.

[carnau]

23 minutes ago, enosez said:

 

So I try the bypass by connecting the yellow and black wire that are on the ignition key and try the re-learn process. NOTHING.

Terrible Idea! Reconnect the wires properly and do a 30 minute relearn. Here is how. Also 90% of the time when this happens it is a passlock sensor located in the housing. Replace the housing and relearn the sensor and you won't have any more issues.

Here is the housing you need. https://amzn.to/2E9k4LB

If you want to bypass the passlock install this - https://amzn.to/2E9W6Qo

 

30 Minute Learn Procedure

Important: The vehicle learns the Passlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.

1.) Turn ON the ignition, with the engine OFF.

2.) Attempt to start the engine, then release the key to ON; the vehicle will not start.

3.) Observe the SECURITY telltale; after approximately 10 minutes the telltale will turn OFF.

4.) Turn OFF the ignition, and wait 5 seconds.

5.) Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes; the vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.

6.) Start the engine. The vehicle has now learned the Passlock Sensor Data Code and/or password.

7.) With a scan tool, clear any DTCs, if needed. History DTCs will self clear after 100 ignition cycles.

 

 

[enosez]

Thanks Carnau.

 

I did put it back to the way it was and tried the procedure you posted.

Still nothing.

The security light will not go out.

 

I've been researching and there isnt a lot of info out there that is useful to me. (hence the reason i connected those two wires)

I was thinking of leaving the battery disconnected over night but will this cause the BCM to need to be re-flashed or programmed?

 

 

[carnau]

2 hours ago, enosez said:

Thanks Carnau.

 

I did put it back to the way it was and tried the procedure you posted.

Still nothing.

The security light will not go out.

 

I've been researching and there isnt a lot of info out there that is useful to me. (hence the reason i connected those two wires)

I was thinking of leaving the battery disconnected over night but will this cause the BCM to need to be re-flashed or programmed?

 

 

No. Just think of all the vehicles that have batteries that die. They would all have to have BCM's reprogrammed lol. I know there is a lot of info out there but trust me it is not as useful as you think. A lot of the times even on these forums I shake my head at some of the comments made from people that have no idea what they are talking about to people who have no idea they don't know what they are talking about. lol.

 

This is what I do for a living. I am a GM tech. Been a tech now at the same dealership for 20 years. If I tell you something you can take it to the bank. I'm not saying I know everything and I am always willing to learn... But before I go connecting wires and burning harnesses up, I would fix it the right way.

 

What codes do you have now that everything is hooked back up correctly.

[enosez]

I put the battery charger on the battery so I dont kill the battery.

I tried doing it with 10 minute intervals (as per timer)

I tried with longer intervals.

I even tried with key on until the security light goes out.

The light never goes out.

How long is too long with the key in the on position waiting for the light to go out?

(And does it matter that the engine tries to start (Turns over))

 

Not sure if I'm doing something wrong or if Im just f****d and need to go to a shop now.

 

Edited February 14, 2019 by enosez

[enosez]

Checked today with a mt2500 scanner. 

Here are the codes I got

 

on the engine P1518

on the BCM current code was B2948 with the following history codes:

B0951. B1440. B2600. B2615. B2625. B2948. B2957. B2958. B3031. U1000 U1305. U1016. U1024

on the IPV history codes U1016. U1024. U1000

 

i was able to clear all codes and the security light went out. 

When I try to start the truck it cranks but does not start. 

 

When i chexk on the scanner in BCM mode it’s showing Passlock power on. Run/crank on and shows key in ignition. 

 

Still wont start. 

Do I need to do key relearn now or is it something else?

[sefiroxx]

Hmmm, Need fsm to verify if starter is locked out via passlock.

 

Typically, if cranking, usually a sign that security is not locking out. Need to do std check on spark, fuel.

 

BTW, very very very few of us have codes memorized so add short description when posting

 

 

[Ak_grown]

it is the original ignition switch? has it been replaced? they are known for going out and having poor contacts with age, which could cause the passlock to act up.

[carnau]

On 2/14/2019 at 3:55 PM, enosez said:

Checked today with a mt2500 scanner. 

Here are the codes I got

 

on the engine P1518

on the BCM current code was B2948 with the following history codes:

B0951. B1440. B2600. B2615. B2625. B2948. B2957. B2958. B3031. U1000 U1305. U1016. U1024

on the IPV history codes U1016. U1024. U1000

 

i was able to clear all codes and the security light went out. 

When I try to start the truck it cranks but does not start. 

 

When i chexk on the scanner in BCM mode it’s showing Passlock power on. Run/crank on and shows key in ignition. 

 

Still wont start. 

Do I need to do key relearn now or is it something else?

The P1518 is a tac module communication fault which will have to be repaired in the future and possibly first before the vehicle will crank because the communication issue may not let the theft system relearn. But we are going to see what we can do, before doing that.

 

DTC B2948 Security System Sensor Power Circuit High

This is the reason the vehicle will not relearn. This is what happens when the code is set.

1.) The BCM stores DTC B2948 in memory.

2.) The vehicle will start and run.

3.) The SECURITY indicator remains illuminated

 

Lets get this code fixed first so we can attempt to relearn the system.

 

First, At the pass lock sensor on the ignition lock case. Test the red/white wire for power using a test light (non led preferably. The cheapest test light you can find will be the best test light). 

 

It should light the test light. If it doesn't let me know on here and I will trace down the power source/fuse for you and we can move in that direction.

 

We need to get the cause of the B2948 repaired before relearning will be possible. It could have been shorted out, or possibly could have shorted out the BCM when you connected wires together.

 

Please quote me on here so it gives me a notification letting me know you returned a comment for me to check.

 

 

 

[enosez]

On 2/21/2019 at 6:48 PM, carnau said:

The P1518 is a tac module communication fault which will have to be repaired in the future and possibly first before the vehicle will crank because the communication issue may not let the theft system relearn. But we are going to see what we can do, before doing that.

 

DTC B2948 Security System Sensor Power Circuit High

This is the reason the vehicle will not relearn. This is what happens when the code is set.

1.) The BCM stores DTC B2948 in memory.

2.) The vehicle will start and run.

3.) The SECURITY indicator remains illuminated

 

Lets get this code fixed first so we can attempt to relearn the system.

 

First, At the pass lock sensor on the ignition lock case. Test the red/white wire for power using a test light (non led preferably. The cheapest test light you can find will be the best test light). 

 

It should light the test light. If it doesn't let me know on here and I will trace down the power source/fuse for you and we can move in that direction.

 

We need to get the cause of the B2948 repaired before relearning will be possible. It could have been shorted out, or possibly could have shorted out the BCM when you connected wires together.

 

Please quote me on here so it gives me a notification letting me know you returned a comment for me to check.

 

 

 

Thanks for the help. Finally had some time to work on it. 

 

The yellow wire has nothing. 

The  red wire with white stripe has power with key in on position

 

I checked for fuel at the fuel rail and had none. I changed the fuel filter as I don’t know when it was changed last. Checked fuel rail again and nothing but a dribble. 

I checked to make sure all relays were seated correctly and still nothing. 

 

The security light is back on solid. 

[carnau]

Need to replace the housing. The relearn the theft and you should be on your way.

 

As long as B2948 is current, you will not have any fuel pressure. It disables the fuel pump.

 

Housing - https://amzn.to/2Hf08ZC

 

 

[enosez]

On 3/4/2019 at 9:17 AM, carnau said:

Need to replace the housing. The relearn the theft and you should be on your way.

 

As long as B2948 is current, you will not have any fuel pressure. It disables the fuel pump.

 

Housing - https://amzn.to/2Hf08ZC

 

 

So I wanted to give an update....

 

I ended up bringing the truck into the dealer. They found that the connector to the fuel pump was replaced by the previous owner and they only twisted the wires together and used tape. The dealer replaced the connector and made proper splices. Truck starts, runs and drives. So far so good.

[Hatemytruckrightnow]

Hey carnau... I know old post...but closest to my problem....have 01 sierra, passlock happened, tried relearn code several times, broke ignition column doing so,  replaced that and housing, did relearn again, got security light to go out, but truck wont stay running.....gives u1000 and u1064 codes.

What can I do next besides set fire to truck lol? But seriously, at wits end

Edited October 23, 2019 by Hatemytruckrightnow

[Dburns]

Having the same issue. Changed housing and tried relearn several times. My antilock theft light went off but truck still wont start. Have a scanner but it cant locate vin#. Will i have to reflash?

[JJP442]

On 2/13/2019 at 7:35 PM, carnau said:

Terrible Idea! Reconnect the wires properly and do a 30 minute relearn. Here is how. Also 90% of the time when this happens it is a passlock sensor located in the housing. Replace the housing and relearn the sensor and you won't have any more issues.

Here is the housing you need. https://amzn.to/2E9k4LB

If you want to bypass the passlock install this - https://amzn.to/2E9W6Qo

 

30 Minute Learn Procedure

Important: The vehicle learns the Passlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.

1.) Turn ON the ignition, with the engine OFF.

2.) Attempt to start the engine, then release the key to ON; the vehicle will not start.

3.) Observe the SECURITY telltale; after approximately 10 minutes the telltale will turn OFF.

4.) Turn OFF the ignition, and wait 5 seconds.

5.) Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes; the vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.

6.) Start the engine. The vehicle has now learned the Passlock Sensor Data Code and/or password.

7.) With a scan tool, clear any DTCs, if needed. History DTCs will self clear after 100 ignition cycles.

 

 

Does the 30 minute reset work or is still needed if the truck starts after the first 10 minutes?

My truck is an ‘01 Yukon with 278,000 miles.

I’m wondering if it’s just time to replace the housing you mention due to age and mileage.

 

TIA,

Big John NYC