GM Service Manual Online
For 1990-2009 cars only

Object Number: 331287  Size: MF
Body Control Module Components
Cell 100: Headlights (Deville USA)
Body Control System Connector End Views
Handling ESD Sensitive Parts Notice
Power Distribution Schematics
Power Distribution Schematics

Circuit Description

The body control module (PZM) commands the high beams through a discrete output to the high/low beam headlamp control relay. When the headlamps relay is energized the high/low beam headlamp control relay provides a power source to either the low beams or the high beams.

Conditions for Setting the DTC

The commanded state of the high beams does not match the feedback state.

Action Taken When the DTC Sets

The PZM continues to command the state requested until the instrument cluster revokes the request.

    • When the measurements are requested in the diagnostic table below, use the J 39200 Digital Multimeter (DMM) with the correct terminal adapter from the J 35616 .
    • When a proper connection is requested, refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.
    • When a wire, connector or terminal repair is requested, use the J-38125 . Refer to Wiring Repairs in Wiring Systems.

Step

Action

Value(s)

Yes

No

1

  1. Turn the headlamp switch to the ON position.
  2. Remove the high/low beam headlamp relay.
  3. Measure the voltage to ground from the high/low beam headlamp relay terminal C9 (ORN/BLK).

Is battery voltage measured?

--

Go to Step 2

Go to Step 6

2

Measure the voltage from the high/low beam headlamp relay terminal C9 (ORN/BLK) to terminal D7 (BLK/WHT)

Is battery voltage measured?

--

Go to Step 3

Go to Step 4

3

Replace the high/low beam headlamp relay.

Is the relay replacement complete?

--

Go to Diagnostic System Check - Lighting Systems

--

4

Inspect CKT 1969 (BLK/WHT) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 1969 OK?

--

Go to Step 5

Go to Step 7

5

Replace the body control module. Refer to Body Control Module Replacement in Body Control System.

Is the body control module replacement complete?

--

Go to Diagnostic System Check - Lighting Systems

--

6

Repair the open or short to ground in CKT 40 (ORN/BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - Lighting Systems

--

7

Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Diagnostic System Check - Lighting Systems

--