Wiring, Stereo & Electronics Audio Components | Radars | Alarms - and things that spark when they shouldn't

Help - bcm

Thread Tools
 
Search this Thread
 
Old Oct 19, 2021 | 08:07 AM
  #1  
INARCTIC's Avatar
Thread Starter
Teching In
 
Joined: Jul 2021
Posts: 5
Likes: 1
From: Ft Wayne, IN
Default Help - bcm

New to owning a LS1 (2000 WS6), but recently, my car had been running fine, then out of the blue one day, I started it, and it ran for about 5 seconds, then shut off, like the fuel is being shut down. It always starts fine, then just shuts down. Everything else works on the car electronically. The shop is telling me that the BCM is bad and is not recognizing the key chip. Is this something that happens, and also, is there a remedy. The shop is telling me that the BCM's for this car are no longer made, so what are my options? Thank you in advance for any insight.
Reply
Old Oct 20, 2021 | 09:20 AM
  #2  
WhiteBird00's Avatar
Ungrounded Moderator
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (4)
 
Joined: Nov 2003
Posts: 11,332
Likes: 347
From: Jacksonville, FL (originally from Toronto Canada)
Default

Your shop is referring to VATS - Vehicle Anti-Theft System - which is contained in the BCM (Body Control Module). VATS disables the fuel enable signal to the prevent the car from running which would cause symptoms as you describe. But it would also disable the starter relay causing the engine not to crank in the first place and it illuminates the SECURITY light in the instrument panel (which you didn't mention).

Now, if it is a VATS problem then you have other options besides replacing the BCM. The PCM (Powertrain Control Module) can be programmed to ignore the lack of a fuel enable signal but that could be an expensive solution if you're not planning other performance mods which require additional programming anyway.

It could be something as simple as dirt and grime on the key resistor pellet and/or inside the ignition cylinder. You can try a spare ignition key if you have one or clean the key pellet contacts with a pencil eraser followed by rubbing alcohol. The ignition cylinder can be cleaned with spray electronic cleaner and a cotton swab or pipe cleaner.

If that doesn't work and you still suspect that VATS is the problem then you can do a VATS bypass. There are plenty of threads in this forum on how to do a bypass... a search for VATS bypass will get lots of results. There are 15 different resistor values used for VATS by GM (actually only 14 of them were used in f-bodies but that doesn't help much). Start by measuring the resistance of your existing key and selecting the value which most closely matches. If that doesn't work then you may have to go through the other values one by one until you find the one that works. There are kits you can buy which have all the possible resistor values included - some even have a box with a simple **** to make selection easy.

I would try those things before I'd even consider replacing the BCM. GM has discontinued the original BCM but there are places that sell refurbished ones. I even saw them on Amazon a while ago.
Reply
Old Oct 20, 2021 | 02:06 PM
  #3  
INARCTIC's Avatar
Thread Starter
Teching In
 
Joined: Jul 2021
Posts: 5
Likes: 1
From: Ft Wayne, IN
Default

Originally Posted by WhiteBird00
Your shop is referring to VATS - Vehicle Anti-Theft System - which is contained in the BCM (Body Control Module). VATS disables the fuel enable signal to the prevent the car from running which would cause symptoms as you describe. But it would also disable the starter relay causing the engine not to crank in the first place and it illuminates the SECURITY light in the instrument panel (which you didn't mention).

Now, if it is a VATS problem then you have other options besides replacing the BCM. The PCM (Powertrain Control Module) can be programmed to ignore the lack of a fuel enable signal but that could be an expensive solution if you're not planning other performance mods which require additional programming anyway.

It could be something as simple as dirt and grime on the key resistor pellet and/or inside the ignition cylinder. You can try a spare ignition key if you have one or clean the key pellet contacts with a pencil eraser followed by rubbing alcohol. The ignition cylinder can be cleaned with spray electronic cleaner and a cotton swab or pipe cleaner.

If that doesn't work and you still suspect that VATS is the problem then you can do a VATS bypass. There are plenty of threads in this forum on how to do a bypass... a search for VATS bypass will get lots of results. There are 15 different resistor values used for VATS by GM (actually only 14 of them were used in f-bodies but that doesn't help much). Start by measuring the resistance of your existing key and selecting the value which most closely matches. If that doesn't work then you may have to go through the other values one by one until you find the one that works. There are kits you can buy which have all the possible resistor values included - some even have a box with a simple **** to make selection easy.

I would try those things before I'd even consider replacing the BCM. GM has discontinued the original BCM but there are places that sell refurbished ones. I even saw them on Amazon a while ago.
Thank you for the in depth response. I do only have the one key for the car, but after taking with the shop, he is going to have the VATS bypassed, he said that should do the trick. Thanks again for your insight.
Reply




All times are GMT -5. The time now is 04:21 PM.

story-0
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-1
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-2
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-3
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-4
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-5
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-6
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-7
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-8
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-9
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE