And when it finally did not start what was the status of the “theft” light? Has a “key-relearn been tried? has the “long period” key relearn been tried”
Error codes do not mean replace a part they are to be used in conjunction with other testing.
I recently worked on a 2005 Chevrolet 2500 Diesel. All we did was fix some fuel leaks, we went to start the truck and the “theft” light was illuminated (I got called in to the job after much head scratching by the fuel system guys) After 3 long period key re-learns the truck finally exited “theft” mode and started. It’s very easy to make mistakes with PassLock and start replacing parts.
I am the type of mechanic trained to fix the system as designed (which takes understanding how it works) and not immeditaly look for ways to by-pass the system. Like I have previously stated if your truck is in “theft” mode the by-pass procedure is immensely more complicated.
And like I stated there are many Internet videos about by-passing PassLock and you can find telephone numbers of companies that sell by-pass kits with technical help desks. You can run your trucks status by them and ask if their product will help.
You don’t need to be diverted from your path to repair because one person says they did not find the information available on the web helpful to them.
Oh yes I am GM trained in PassLock repair, ASE Certified and GM Certified in electrical systems repair (from their Specialized Electrical training Course) and also BMW trained in specialized electrical (body systems repair)
You can’t produce the signal required by the PCM using only resistors. Although, for the fixed frequency 30/50Hz version, it is a simple circuit.
Well, that’s a catch-22, isn’t it? If they make the system easy to defeat so people who don’t want it can eliminate it, it also makes it easy for a thief to do the same.
One way we can all benefit from security systems being standard equipment is through reduced insurance rates. However, it has an unintended consequence in that criminals who want your car may have to resort to more violent means to get it. As security systems become more prevalent and sophisticated, car-jackings are likely to increase IMO.
Yes it could say “security” if the short relearn does not work try the 1 hourx3 relearn and be sure to have all the doors shut when doing the re-learn (procedure is in Factory Service Manual)
Hey it’s worth a shot, it just involves leaving the key in certain positions for certain amounts of time
Other than the security light, were you having any other issues, antilock brakes, airbag, ETC? The reason I took the communications class was cause my antilock brakes worn’t working, also a half a dozen or so communication codes were being thrown. The Instrument panel was acting erratically also the Theft light would blink and stay on at times. I couldn’t figure it out cause if I put a lab scope on the Class 2 data line I got a nice square wave. Find out what the codes are. It could be as simple as a bad ground, as it was for me. The ground was good enough for continuity, but not to carry the current needed for the EBCM to function properly. It would therefore send out confusing info to the other modules causing them to malfunction. I never had a problem with starting, but every once and a while the engine would turn off, but restart if I turned the key to off then back to the start/run position. The reason being is that the BCM wakes all the other modules up (usually with a continuos 7 volt signal across the Class 2 data line) and I think the PCM would reset when it got the signal from the ECBM, then would need to be “woken up” by the BCM again. If you have communication codes I would check ground and power to all the modules (make sure to check grounds under load I.E. with a headlight or test light.) Also hook a lab scope up to the data line and see if there is a nice square wave. NOTE: DO NOT check data line with instrumentation that has less than 900 ohm resistance. I would also Check the data line for the “wake up” signal. You do this by hooking up the lab scope to the data line with the key in off, place the scope somewhere you can see it from the interior and then turn the key to the on position. Let us know what you find out, also I have a list of communication codes and what they pertain to if you need it. let me know.
Since no other electronic functions are malfunctioning, I can’t believe that the problem is related to a bad ground which logically would reflect itself in lots of areas.
Unfortunately I had had the truck already towed to the local mechanic, 1 of the 2 available parts purchased and installed as of yesterday. Assuming that there hasn’t been intervention from above between yesterday evening and this morning, I’ll most likely take the $ spent thus far on the chin and get the truck to someone as you suggest as quickly as possible. It just so happened that I may have a line on the sort of mechanic you reference as a function of an article in the New York Times about healthcare that interviewed a small business (mechanic shop) in Wheat Ridge, CO who I in turn Googled and came up with stellar credentials. I’ll keep you all posted.