Diagnostic Routine M

Diagnostic Routine M

Diagnostic Overview

All The Stoplamps Are Inoperative

Refer to Wiring Diagram Set 90 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

REFER to Stoplamps .

REFER to Stoplamp Switch .

Visual Inspection and Diagnostic Pre-checks

- Inspect the BCM (Body Control Module) fuse 15 (15A) (stoplamps).

- Inspect the BJB (Battery Junction Box) fuse 59 (10A) (stoplamp switch).

- Inspect the stoplamp switch for damage.

Pinpoint Test

1. CHECK THE STOPLAMP SWITCH VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Disconnect: Stoplamp Switch.

3. Measure:





Is the voltage greater than 11 volts?








2. BYPASS THE STOPLAMP SWITCH

1. Connect a fused jumper wire:





Do the stoplamps illuminate?








3. CHECK THE STOPLAMP SWITCH INPUT CIRCUIT TO THE BCM (Body Control Module) FOR AN OPEN

1. Disconnect: BCM (Body Control Module) C2280B.

2. Measure:





Is the voltage greater than 11 volts?








4. BYPASS THE BCM (Body Control Module)

NOTE: If the jumper wire fails, refer to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams. After the repair:If DTC (Diagnostic Trouble Code) U1000:00 is present, clear the DTCs (Diagnostic Trouble Codes) and repeat the on-demand self-test (required to enable the stoplamp output driver if DTC (Diagnostic Trouble Code) U1000:00 is present).
If DTC (Diagnostic Trouble Code) U3000:49 is present, install a new BCM (Body Control Module). REFER to Body Control Module (BCM) - without Intelligent Access (IA) or REFER to Body Control Module (BCM) - with Intelligent Access (IA) .

1. Disconnect: BCM (Body Control Module) C2280D.

2. Connect a fused jumper wire:





Do the stoplamps illuminate?








5. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Disconnect and inspect all BCM (Body Control Module) connectors.

2. Repair:

- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary

3. Reconnect the BCM (Body Control Module) connectors. Make sure they seat and latch correctly.

4. Operate the system and determine if the concern is still present.

Is the concern still present?