PCM B1631 Computer Code
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,517
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From: Lafayette Louisiana
PCM B1631 Computer Code
After stopping at the store last night. My 2004 would not start. All gauges and stuff came on normally, but no start, not even a click. I tried a few times and nothing. Turned on the headlights just to make sure battery was good. Looked fine, tried again and it started right up. This moring I checked computer codes. It showed a PCM B1631 - History. That indicates something about a Security System password. Just wonder if I should be concerned about this or what might have caused it ??
Team Owner
Joined: May 2006
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
After stopping at the store last night. My 2004 would not start. All gauges and stuff came on normally, but no start, not even a click. I tried a few times and nothing. Turned on the headlights just to make sure battery was good. Looked fine, tried again and it started right up. This moring I checked computer codes. It showed a PCM B1631 - History. That indicates something about a Security System password. Just wonder if I should be concerned about this or what might have caused it ??
P1631 Theft Deterrent System Password Incorrect
It could be that your key's resistor is not working correctly.
Here is the procedure to relink the Vats:
http://www.hptuners.com/forum/showthread.php?t=16632
Here is a Tech article with trouble shooting guide:
http://www.gearchatter.com/viewtopic9949.php
Here is an article I found on a denali with a similar problem:
http://findarticles.com/p/articles/m...16139222/pg_3/
Let us know any more info and if this is helping in the correcting of the problem.
Thanks,Matt
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,517
Likes: 159
From: Lafayette Louisiana
Thanks Matt, You are right it was a P code. There was one other code from HVAC B0361 ... guess a got stuck on B's. Anyway, everything seems fine with the P1631 now. Car is running fine. The HVAC code keeps coming back but always show history. I'll post that in a seperate thread. Thanks again for your help.
Seth
2004 Lemans Commemerative Convertible
Seth
2004 Lemans Commemerative Convertible
Drifting
Joined: Jul 2007
Posts: 1,365
Likes: 1,818
As Matt says, it's P1631. Basically the VATS system failed to correctly read the resistance value of the pellet on your key. Try cleaning it with the eraser on a pencil and then wipe off the pellet with a clean cloth. Might also get some electrical contact cleaner from Radio Shack. Squirt a little in the ignition key slot and then insert and withdraw the key 8 or 10 times wiping off the key before the next reinsert. There is a fine wire in the key slot that wipes across the pellet on the key to read it. If it is not read and correctly matched against a value stored in the computer, the starter and fuel are disabled to help prevent a theft of the car. The wire may be a little tarnished. Also try your backup key.
