2003 Silverado passlock 2 issues

Is it setting an enhanced code?

No codes, no security light. I've tried a new key switch also and have done the relearn sequence several times.

I was going to offer that a 1632 means the ign cylinder has a reading problem. Those can be bypassed by rewiring with a resistor added. but if there is no code or warning light, your concern could be before the key is read in the system's "mental map". You know the guy who invented the bypass idea for all the passlock read problems says it is a very difficult system to find experienced help for. I can suggest finding the vehicle service manual at the GM dealer to read, noone else reads it. They wont miss it for a few days, you can ask them about service bulletins that apply and ignition switch issues as well. Gotta be your best help.

Thanks for the advice. I've bout pulled my hair out tinkering with this. Now that it is getting colder her in the mountains of NC it is getting harder to start in the mornings pulling the battery cable loose. A mechanic friend of mine told me today to try pulling the radio out but that didn't work either, and he said he would try to diagnose for me when he got a minute, but he thought it would probably be something in the BCM. I pulled it out this evening (again) and did my best best to check for wiring issues. After reinstalling, the radio didn't go into locked mode but still wouldn't start (started locking again after that BCM reinstall).

Y'kno, the enhanced code feature of a code reader is not always where it automatically takes you during its read sequence. we had to toggle thru some stuff and keep reading the directions for the olds I last checked and had a no start,security light lit, key on, wait 4 minutes, security light goes off, start engine, drive to parts store security light comes back during the trip but engine runs. No codes, then search directions for enhanced check and get a key reader concern, turns out, behind radio theres 2 wires. apply fix of adding resistor etc. Found it by googling it and reading till my eyes were dry. Resistor available as well as basic tools and supplies for electric repair. Customer never did listen, just kept waiting with the key on and then starting. they decided to sell the car. do not know after that.

Sounds like I have a little more reading to do. I appreciate your insight on this!

If the BCM keeps locking the radio, is it possible the Tech 1 type tool for your vehicle's vintage is the unlock? Security system issues with car computers almost guarantee you need the dealer's help by this method. it gives their customer enhanced security by making it necessary to consult them? Kinda like my mercedes, everyone wants money, but very few have a decent part and the ability to duplicate the electronic decoding or the machine to make a duplicate key or unlock a security module unless they are bigger thieves.

We had taken battery off of 2000 chevy Silverado and put it back on after three hours. My truck never had a problem starting until this. So my husband said turn the key all the

Way forward without cranking it. Wait fifteen minutes and tadah it cranked right up.

"Tadah", that means it only will start with the emergency procedure during that occurrance.. That also means the diagnostics can begin. The alternative is a bypass you can elect to do. Without it, This problem can repeat and have you unable to start it when you need to.

Changing batteries would have merely caused the computer to reset for a passlock equipped vehicle as it involves memory. The symptom suggests a code was set. it would likely be a wrong key error code, or unable to read the key code available to your tech during a reading of enhanced codes. your waiting more than 4 minutes until the security light goes off, then cycling the key and starting suggests you reset the passlock security shutdown, but the enhanced code can still be pulled with a proper scan tool. then you can find what tests are needed.

You can pull the code at your parts store using their scan tool, write it down and its definition, then wait and see if there is any recurring issue.

Hello, i have been fighting the security issue as well, here is an item that is suppose to bypass and it is pretty cheap if it fixes problems, I'm going to order one and see...I have no security light, but can hear a noise like an actuator moving behind the key...my doors on drives side will lock but doesn't line up due to body damage..

Brought my 03 Silverado to Jack Ferrier western tire & auto care, they bypassed the security system and it works great now. Now my security system is on my hip!