1998 Silverado Passlock Issue ---- ugh

[s98gmc]

Once you turn it off in the PCM you can Huck the passlock module. The PCM no longer seeks a signal from it.

Good to know. The tuner cautioned me the security light may still blink at key on so I pulled the bulb from the cluster.

 

[HotWheelsBurban]

I was told that about the bulb too. Had the PL tuned out last fall, and it'll be on sometimes. Then goes off for a while, but as long as the truck starts, the light doesn't bother me!
Pinger, I think that a remote switch is a good idea for your truck. Probably a good idea for any truck on propane, since as you pointed out that the fuel pump doesn't need to be on when no petrol is needed to run the engine.

 

[Supercharged111]

I was told that about the bulb too. Had the PL tuned out last fall, and it'll be on sometimes. Then goes off for a while, but as long as the truck starts, the light doesn't bother me!
Pinger, I think that a remote switch is a good idea for your truck. Probably a good idea for any truck on propane, since as you pointed out that the fuel pump doesn't need to be on when no petrol is needed to run the engine.

The PL module is the one causing the light, not the PCM. If the PCM is happy, the truck will run.

 

[jmw201]

Hello,
I'm hoping someone may be able to help me on what I think is a passlock issue...

I go to start the truck, and it will start and run for a second or two.. then shutoff... passlock light flashes when the truck shuts off.

Now, I tried to do the 10/30 minute passlock relearn procedure.. Heres what I do.

- I attempt to start
- then leave in the on position for ten minuets
-The instructions say the security light should stay on.

The problem I have is the light will not stay on, so I cannot seem to get it in relearn mode. When I attempt to start, the security light will come on and flash for a few seconds, and then goes off.

Any help would really be appreciated. This truck is super frustrating.

Hi
I know th is an old thread but how did you fix your truck? Mine is like yours where the security light doesn't stay on during the relearn. Did you go with the suggested by pass route? Thanks

 

[HotWheelsBurban]

Hi
I know th is an old thread but how did you fix your truck? Mine is like yours where the security light doesn't stay on during the relearn. Did you go with the suggested by pass route? Thanks

The ONLY WAY to get rid of the Passlock system is to have it electronically deleted from the PCM. The relearn procedures work, a couple of times and then don't work anymore. The resistor install works, until the resistor changes resistance after a while. And with it you have to hack up your ignition wiring....
I went through this with my '99 Suburban, and I think the Burb was having issues with that as far back as 2013 when we bought it. Because it would start right up, and keep behaving normally, and then it'd get a notion to not start. Let it sit a while, you could usually get it to start...till the next time it got notional. This was one of the reasons we didn't drive it much; it was initially purchased to be a weekend/swap meet truck. Then we needed to drive it more often, as the daily drivers were giving us trouble.
Then in summer 2019 it really got bad about it. We spent $$$ on rental cars because every time someone needed to go to work, that's when it would act stupid. Finally got some answers from a shop we used, after they couldn't figure it out either. They suggested the PCM delete, and a shop that could do it. My brother and I had tried, 3 or 4 times a day, for a couple of weeks, to get it to start and stay running, and then one evening I tried it and lo and behold it started and stayed running! It hesitated a moment, like it was asking me,"okay Mom is this what I'm supposed to do?" So the next morning it starts again, so we headed to the suggested shop. They had it about an hour, and charged me $250, but that was in October 2019 and we've not had any more trouble with the Passlock system.