Where is the Theft Deterrent Module located? BCM

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My car doesn't start I by-passed the VATS system but it still want start. I was told I need to replace the Theft Deterrent Module in order to start my car. But I don't know where it's located. Also does it need to be reprogrammed after I replace it?

I am still having trouble with the same car 97 Pontiac Bonneville. I need to remove the BCM ( Body Control Module). I have located it, but I am having trouble removing it in order to get the part number to get the replacement. PLease tell me how to remove it without causing any damage to the BCM? Thanks

Do you
have the same problem?
Friday, December 16th, 2011 AT 5:15 AM

4 Replies

  • 64 POSTS

I finally was able to remove the BCM it was actually very simple! Can you tell me where the anti-theft module is located? Or the TCM (theft control module? Even though I had a professional to bypass the VATS system is it possible he got it wrong, because my security light still flashes. And everything that I have read tells me that my problem is dealing with security system and having the right OHM. Please don't miss understand me I really appreciate all of your assistance

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Thursday, December 29th, 2011 AT 11:06 PM
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Here is what I found on the TCM and the BCM is located in the passengers foot well, (diagram below) and the TCM is located behind the dash on the passages side. Below.

If the PASS-Key II module is bad, it should be replaced with a new PASS-Key II module. It is not necessary to match the replacement PASS-Key II module to the ignition key. The replacement PASS-Key II module "learns" the ignition key code (resistance value) the first time it is turned on. The ignition key code is "learned" permanently, so caution should be used to ensure that unwanted key codes are not "learned."
If a fault is detected in the system wiring, or if a defective key is used, the replacement module does not "learn" the key code and the "SECURITY" indicator flashes at a rate of once per second while the ignition is on to indicate a fault.

The BCM is located in the passengers foot well, (diagram below)


WARNING: Deactivate air bag system before performing any service
operation. See AIR BAG RESTRAINT SYSTEM article. DO NOT
apply electrical power to any component on steering column
without first deactivating air bag system. Air bag may deploy.
Body Control Module (BCM) may also be referred to as Multifunction Alarm, Lock & Lighting (MALL) module.
The Multifunction Alarm, Lock and Lighting (MALL) controls different body systems by obtaining information from various sensors and switches, then using this information to command the output to
each body system. MALL module provides a set of internal service diagnostic features to assist technician in troubleshooting electrical short conditions that may affect MALL. If electrical short
occurs during vehicle operation, MALL module stores history codes. These codes can be accessed by entering MALL module diagnostic mode. After providing history codes, MALL module enters
Input/Output (I/O) mode. I/O mode enables verification that inputs to MALL module are functioning properly.


Location Under Right Side Of Instrument Panel, Near
Glove Compartment Attached To Left Front Door Pillar
Under Right Rear Seat Cushion


Check PWR DR LK fuse (15- or 20-amp) and INT LP (20-amp) fuse in RH rear junction block.

Check for poor terminal contacts at component and harness connectors.
Check for proper installation of aftermarket electronic equipment which may affect other systems.
Check for broken or partially broken wire inside insulation which could cause system malfunction but check good in continuity/voltage check.


Turn ignition switch to ON position. Depress and hold power door UNLOCK switch. Cycle headlights 6 times within 20 seconds of depressing UNLOCK switch. Release power door lock
UNLOCK switch.

MALL module will sound stored history codes by audible bongs. Number of bongs correspond to history code number. FASTEN BELTS indicator flashes with each bong. MALL module
will cycle through history codes 3 times, pausing 2 seconds between cycles. If no history codes exist, MALL will immediately enter input/output mode. History codes may be erased by
holding power door unlock switch for four seconds. See MALL HISTORY CODES table for identification and description. To exit diagnostic mode, turn ignition switch to OFF position or
accelerate vehicle above 8 MPH.

While in Input/Output mode, each input to MALL module can be tested by activating/deactivating input device (door lock switch, seat belt switch, etc.). Each input transition is acknowledged with a
single bong with a simultaneous flash of FASTEN BELTS indicator. See MALL INPUTS/OUTPUTS table for inputs and outputs that should be checked.
Keyless Entry (RKE) I/O Mode Feedback

When using RKE transmitter, audible feedback is different when activating MALL inputs power door lock switch, transaxle gear selector and keyless entry unlock. Each input is acknowledged with
2 bongs with simultaneous flashes of FASTEN BELTS. On Bonneville, no bongs will occur when shifting into Park position, due to ignition-OFF door unlock feature.


CAUTION: To prevent damage to terminals, Connector Test Adaptor Kit (J-
35616-A) must be used whenever a diagnostic procedure requires checking or probing terminals. To locate and identify terminals,

Check operation of power door lock system. Move left door lock/window switch to LOCK, then UNLOCK position. Move right door lock/window switch to LOCK, then UNLOCK
position. When each switch is activated, all doors should lock and remain locked until UNLOCK switch is depressed, which should unlock all doors. If some door lock functions do
not operate as specified,

If all power door lock functions are inoperative Check operation of Remote Keyless Entry (RKE) system. If some RKE functions do not operate as specified, see REMOTE KEYLESS ENTRY SYSTEM article?

Depress Door LOCK Button
Depress Door UNLOCK Button Once
Depress Door UNLOCK Button Twice
Within 4 Seconds
Depress TRUNK Release Button
Depress PANIC Button
Depress Any Button
Result All Doors Should Lock
Driver's Door Should Unlock
All Doors Should Unlock
Rear Trunk Lid Should Open Horn Should Sound & Lights Should Flash
Selected Function Should Actuate Doors Should Lock When Shifted Out Of Park &
Unlock When Shifted Into Park
Shift Transmission In & Out Of Park

Using Remote Keyless Entry (RKE) transmitter.

Check operation of interior lighting system. See INTERIOR LIGHTING SYSTEM DIAGNOSTIC CHECK table. If some interior lighting functions do not operate as specified, If all interior lighting functions are inoperative

Depress UNLOCK Button On RKE Transmitter
With All Doors Closed, Move Interior Light Switch To ON Position
Result Courtesy Lights Should Illuminate For 40
Courtesy Lights Should Illuminate
Courtesy Light Should Illuminate For 25 Seconds, Then Fade Out
All Interior Lights Should Illuminate For 25
Seconds, One At A Time

Open & Close Each Door One At A Time
With All Doors Closed, Lift Each Door Handle
Close All Doors. Turn Ignition Switch To RUN, then OFF Position. Remove Key

Then Fade Out Light Should Illuminate For 25
Seconds, Then Fade Out Cigarette Lighter(s) Should Pop Up & Heating
Element Should Be Red Hot Glove Box Light Should Illuminate
Rear Compartment Light Should Illuminate
Depress Cigarette Lighter(s)
Open Glove Box
Open Rear Compartment Lid
Move Headlight Switch To Park Position,
Open Engine Compartment Lid Open Each Vanity Mirror
Engine Compartment Light Should Illuminate
Vanity Mirror Lights Should Illuminate

Removal & Installation

Turn ignition switch to OFF position. Disconnect negative battery cable. Locate MALL under right side of instrument panel, near rear of instrument panel glove box. Remove lower instrument panel
sound insulator. Disconnect MALL module harness connectors. Remove MALL module from vehicle.

Please let me know if you need anything else to get the problem fixed.

Best, Ken

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Sunday, April 9th, 2017 AT 11:50 AM
  • 2 POSTS

I have a 1992 Chevrolet Caprice classic, And im having problems trying to replace the Dimmer switch.I really want to know if I have to take the steering wheel off aswell. Ooohhh please send me s blessing!

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Saturday, September 30th, 2017 AT 9:27 PM
  • 13,845 POSTS

Please post your question here


Cheers, Ken

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Sunday, October 1st, 2017 AT 10:46 AM

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