Possible Passlock Issue?

Hey guys,
I'm new to the forums here. Thanks for having me. I have a question about my 2005 Chevy Colorado. Ever since I bought it in January of '06 I have had intermittent starting issues. The longest I have gone without this issue is probably three weeks. What happens is once in a while I will try to start it and the motor spins but it just will not crank. What I usually do is take out the key, get out, shut the door, and let the truck sit for about 10 to 15 minutes and try it again. 90% of the time that works. There have been a couple of instances where I have had to let it sit for more than an hour before it started again.

So the most recent occurrence of this issue was last night. I was about to leave a friends house and he noticed something I never did. When the truck is not starting, the fuel pump never kicks on when you turn the key to the ON position. Usually you hear a short hum or wine sound which he said is the fuel pump getting ready to start the engine. Well, no fuel pump. Also, the lock icon in the dash flashes. So we let the truck sit for about 13 minutes and tried it again. This time I just turned the key to ON before trying to start. We heard the fuel pump that time. Turned the key the rest of the way and it started just fine. So everything is pointing to Passlock issues. The owner's manual says that Passlock "...enables fuel if the ignition lock cylinder is turned with a valid key. If a correct key is not used or the ignition lock cylinder is tampered with, the fuel system is disabled and the vehicle will not start." So, flashing lock symbol on the dash, no fuel pump sound when trying to start, letting it sit for at least 10 minutes and it starts... It all points to Passlock. For some reason the dealership hasn't been able to figure this out...

Every time I take it to the dealer they either say something else was wrong or theres nothing wrong at all. It has had a new battery and ECU installed by the dealership. They've checked the starter, fuel pump, ignition switch, the "computer" for "security codes" and even the gas cap. Now I am to the point that the truck's warranty is over and I am on my own trying to get this fixed.

The frustrating thing is that the issue is intermittent and I am the only one around when it acts up. I once let the dealer keep my truck for two weeks just so that they could try to recreate the issue which they were never able to do. Now when I take it to them its like they don't care anymore. I can just hear the groans from the service department "oh damn.. theres that red colorado again.. what does he want now?" The past 3 times they have had it they kept it for a couple of days, called me back and said theres nothing wrong with it, that they couldn't recreate the problem. Well... I know I'm not delusional and just because they can't recreate it doesn't mean there isn't a problem. But I understand where they are coming from.. if they can't see the problem it makes it very difficult to troubleshoot and fix.

So, I guess what I am looking for is some free advice on how you guys would handle this. Is there anything I can do to completely disable Passlock on the truck just to see if doing so will clear up the issue? Is there something the dealership's service guys can do to fix Passlock or turn it off? Would installing power locks help (as someone else has suggested)?

Sorry I can't help but my father in law is having the same issue with his 2006. Have you figured anything out yet?

Hey guys,
I'm new to the forums here. Thanks for having me. I have a question about my 2005 Chevy Colorado. Ever since I bought it in January of '06 I have had intermittent starting issues. The longest I have gone without this issue is probably three weeks. What happens is once in a while I will try to start it and the motor spins but it just will not crank. What I usually do is take out the key, get out, shut the door, and let the truck sit for about 10 to 15 minutes and try it again. 90% of the time that works. There have been a couple of instances where I have had to let it sit for more than an hour before it started again.

So the most recent occurrence of this issue was last night. I was about to leave a friends house and he noticed something I never did. When the truck is not starting, the fuel pump never kicks on when you turn the key to the ON position. Usually you hear a short hum or wine sound which he said is the fuel pump getting ready to start the engine. Well, no fuel pump. Also, the lock icon in the dash flashes. So we let the truck sit for about 13 minutes and tried it again. This time I just turned the key to ON before trying to start. We heard the fuel pump that time. Turned the key the rest of the way and it started just fine. So everything is pointing to Passlock issues. The owner's manual says that Passlock "...enables fuel if the ignition lock cylinder is turned with a valid key. If a correct key is not used or the ignition lock cylinder is tampered with, the fuel system is disabled and the vehicle will not start." So, flashing lock symbol on the dash, no fuel pump sound when trying to start, letting it sit for at least 10 minutes and it starts... It all points to Passlock. For some reason the dealership hasn't been able to figure this out...

Every time I take it to the dealer they either say something else was wrong or theres nothing wrong at all. It has had a new battery and ECU installed by the dealership. They've checked the starter, fuel pump, ignition switch, the "computer" for "security codes" and even the gas cap. Now I am to the point that the truck's warranty is over and I am on my own trying to get this fixed.

The frustrating thing is that the issue is intermittent and I am the only one around when it acts up. I once let the dealer keep my truck for two weeks just so that they could try to recreate the issue which they were never able to do. Now when I take it to them its like they don't care anymore. I can just hear the groans from the service department "oh damn.. theres that red colorado again.. what does he want now?" The past 3 times they have had it they kept it for a couple of days, called me back and said theres nothing wrong with it, that they couldn't recreate the problem. Well... I know I'm not delusional and just because they can't recreate it doesn't mean there isn't a problem. But I understand where they are coming from.. if they can't see the problem it makes it very difficult to troubleshoot and fix.

So, I guess what I am looking for is some free advice on how you guys would handle this. Is there anything I can do to completely disable Passlock on the truck just to see if doing so will clear up the issue? Is there something the dealership's service guys can do to fix Passlock or turn it off? Would installing power locks help (as someone else has suggested)?


You're in luck - Just about every GM POS car that uses Passlock II system is having the same problem.

We've written a guide that everyone can use... It's for an Impala - but like I said, its the same thing - just slightly different parts (sometimes even the same parts)...

http://www.automotiveforums.com/vbulletin/forumdisplay.php?f=112

have you tried re-programming it? sometimes the bcm will forget especially if the battery is unhooked or dirty terminal.does the fob open the doors? re-program it as the owners manual states and i betting it will make a world of difference