Security light will not go out

[DADSRIG]

Maybe somebody else has encountered my problem.... 01 Chev Duramax: I replaced both batteries at the same time, when I started the engine, the security light comes on the message center and does not go out...Everything works as advertised. No problem with passlock, the engine starts, doors lock and unlock with the key fab. Stereo functions. I tried the passlock relearn, but I think that method is when the engine fails to start....If any one can help.....

[DmaxMaverick]

I ran across this when I replaced my batteries, both at once. Disconnect both batteries, then ground the positive cable for 30 minutes. This should reset the PCM/BCM and wipe the history, as well as the security code. If your radio is locked, be sure you have the code handy or it may not work after. This is essentially a "hard reboot" of the system.

In the future, with any late model vehicle, replace only one battery at a time to prevent this (or supplement 12V during the process if it has only one battery).

[DADSRIG]

Thanks...I'll give it a try...mind you my radio functions properly as well as everything else at this time...I'll post with results...

[DADSRIG]

I tried the method of grounding the positive cable with no help. After reconnecting, the radio presets weren't even gone. The only thing I had to reset was the clock... Apparently getting power from some where else. NextI'll tried to pull codes to see what happens...Any other suggestions????? Thanks in advance.

[DADSRIG]

I ran across this when I replaced my batteries, both at once. Disconnect both batteries, then ground the positive cable for 30 minutes. This should reset the PCM/BCM and wipe the history, as well as the security code. If your radio is locked, be sure you have the code handy or it may not work after. This is essentially a "hard reboot" of the system.

In the future, with any late model vehicle, replace only one battery at a time to prevent this (or supplement 12V during the process if it has only one battery).

When you say to ground the positive cable, you mean either one??...correct?? Both positives should ground the pcm/bcm. Either way, I tryed this...no help. The radio never lost its presets... the clock was the only thing requiring resetting..

[DmaxMaverick]

The radio presets won't be lost, with a power loss. They are stored in NVRAM (like a memory card in a digital camera or thumbdrive).

To wipe the xCM memory, the positive cable (after the batteries are disconnected/removed) on either side needs to be grounded. They are connected, so it doesn't matter which one. 30 minutes should do it, but leave it like this for longer (overnight) to be sure. Also make sure you don't have any accessories connected with its own power supply (not likely, since the clock reset). Once they've been "wiped", they will revert to default.

If the problem persists, then you have an issue with the BCM, wire harness, or a sensor/input. You need to read the PCM/BCM codes and condition to determine the status of the system, during the problem. Unfortunately, you'll need a Tech II to do it (trip to the dealership or equipped shop). It should be simple (but not necessarily cheap) once the system status is charted.

[DADSRIG]

The radio presets won't be lost, with a power loss. They are stored in NVRAM (like a memory card in a digital camera or thumbdrive).

To wipe the xCM memory, the positive cable (after the batteries are disconnected/removed) on either side needs to be grounded. They are connected, so it doesn't matter which one. 30 minutes should do it, but leave it like this for longer (overnight) to be sure. Also make sure you don't have any accessories connected with its own power supply (not likely, since the clock reset). Once they've been "wiped", they will revert to default.

If the problem persists, then you have an issue with the BCM, wire harness, or a sensor/input. You need to read the PCM/BCM codes and condition to determine the status of the system, during the problem. Unfortunately, you'll need a Tech II to do it (trip to the dealership or equipped shop). It should be simple (but not necessarily cheap) once the system status is charted.

Thank you for your reply...I'll give it a shot over night and see what happens. I hope I wont have to visit my friendly neighborhood Chev dealer... Will post with results..

[DmaxMaverick]

You don't have to visit the Chevy dealer. Any fully OBD II equipped competent independent shop can take care of you (most are nowadays). Your issue isn't Diesel specific, so you shouldn't need to visit a Diesel specialized shop, either.

The battery disconnect suggestion is by no means a fix. It will only verify you don't have a "ghost" in the system. It's a necessary diagnostic step. With a Tech II, you would manually clear memory (not requiring a disconnect).

Your security light persistence is curious, though. With no other symptoms, it's very difficult to determine the cause in your driveway. If it were a Passlock issue, you would likely have other effects, like delayed or disabled starting. Could also be a door striker switch fault. Unfortunately, they aren't in the posts anymore. They are built into the latch mechanism in the doors. There are 4 of them, with a crew cab.

If you disconnect for longer, like discussed, and it still persists, try a "security system test". Open a window, lock the system with a key fob (horn chirp), then unlock and open a door manually. The horn should go off and lights flash, like you hit the panic button. Repeat for all doors. If one doesn't react, you may have located the problem.

Just throwing ideas out there. Good luck.

[DADSRIG]

You don't have to visit the Chevy dealer. Any fully OBD II equipped competent independent shop can take care of you (most are nowadays). Your issue isn't Diesel specific, so you shouldn't need to visit a Diesel specialized shop, either.

The battery disconnect suggestion is by no means a fix. It will only verify you don't have a "ghost" in the system. It's a necessary diagnostic step. With a Tech II, you would manually clear memory (not requiring a disconnect).

Your security light persistence is curious, though. With no other symptoms, it's very difficult to determine the cause in your driveway. If it were a Passlock issue, you would likely have other effects, like delayed or disabled starting. Could also be a door striker switch fault. Unfortunately, they aren't in the posts anymore. They are built into the latch mechanism in the doors. There are 4 of them, with a crew cab.

If you disconnect for longer, like discussed, and it still persists, try a "security system test". Open a window, lock the system with a key fob (horn chirp), then unlock and open a door manually. The horn should go off and lights flash, like you hit the panic button. Repeat for all doors. If one doesn't react, you may have located the problem.

Just throwing ideas out there. Good luck.

Thank you. One of the first things I tryed was the security sys ck. It passed for the driver door. I'll attempt for the remainder of the doors. Funny, that I replaced the batteries once before and logically did what you suggested; replace one battery at a time. This time I had to bring the batteries to Walmart at the same time to warranty them...result, the problem at hand...

[DmaxMaverick]

It's hard to say. Some have this problem. Some don't. It may have something to do with the options equipped the way they are.

It could be a matter of start or warm up cycles to clear the light, as long as everything else is functioning normally. Without a DTC, I'm guessing, though. You could have an issue with one of the other door switches, that didn't wake up after the battery swap.

[DmaxMaverick]

This isn't an engine related issue, so I'm moving it to the Accessories Forum.

[db8]

I have the same problem and was wondering if you figured out your problem with the security light on and absolutely no other problems? I too disconnected both batteries at the same time because my middle son wrecked the truck (2002 HD GMC Duramax) and it was getting fixed. This happened a year ago and no issues....just the security light on constantly.

The dealer wants $123 just to put it on the code reader. Thanks. Dave

http://www.thedieselpageforums.com/tdpforum/images/misc/progress.gif

[DickWells]

I thought I had posted on this thread before, but don't see it.
Anyway, my son's security lock light is on constantly, and he's never fixed it. But, a few months ago, I was chasing an instruments issue, and had the plastic housing off, from around the steering wheel. I was checking connectors, and remember unclipping one, over on the right-side, and (I think) behind the key switch, but not sure. I think the connector was white, and I know it was quite small. When I pulled it apart, the security light came on. So, just in case you have the issue, and have tried all the other stuff, it might be good to pop those panels apart, and excercise those connectors in there. It's just an off-chance idea, but maybe worth it. Meanwhile, my boy hasn't seen fit to try that!