Diagnostic Routine N

Diagnostic Routine N

Diagnostic Overview

One Or More Stoplamps Are Inoperative

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

Normal Operation and Fault Conditions

REFER to Stoplamps .

DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Inspect the stoplamps for damage.

- Verify the bulbs are OK.

Pinpoint Test

1. IDENTIFY THE INOPERATIVE STOPLAMP

1. Ignition ON.

2. Apply the brake pedal and observe the stoplamps.

Are all the stoplamps inoperative?







2. CHECK FOR VOLTAGE TO THE HIGH MOUNTED STOPLAMP

1. Ignition OFF.

2. Disconnect: High Mounted Stoplamp.

3. Ignition ON.

4. For 4-door vehicles (with the brake pedal applied), measure:





5. For 5-door vehicles (with the brake pedal applied), measure:





Is the voltage greater than 11 volts?







3. CHECK THE HIGH MOUNTED STOPLAMP GROUND CIRCUIT FOR AN OPEN

1. For 4-door vehicles (with the brake pedal applied), measure:





2. For 5-door vehicles (with the brake pedal applied), measure:





Is the voltage greater than 11 volts?







4. CHECK THE HIGH MOUNTED STOPLAMP SUPPLY CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

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

3. For 4-door vehicles, measure:





4. For 5-door vehicles, measure:





Is the resistance greater than 10,000 ohms?







5. CHECK THE HIGH MOUNTED STOPLAMP SUPPLY CIRCUIT FOR AN OPEN

1. For 4-door vehicles, measure:





2. For 5-door vehicles, measure:





Is the resistance less than 3 ohms?







6. CHECK FOR VOLTAGE TO THE REAR STOPLAMP

1. Ignition OFF.

2. Disconnect: Inoperative Rear Stoplamp.

3. Ignition ON.

4. For 4-door vehicles (with the brake pedal applied), measure:





5. For 5-door vehicles (with the brake pedal applied), measure:





Is the voltage greater than 11 volts?







7. CHECK THE REAR STOPLAMP GROUND CIRCUIT FOR AN OPEN

1. For 4-door vehicles (with the brake pedal) applied, measure:





2. For 5-door vehicles (with the brake pedal) applied, measure:





Is the voltage greater than 11 volts?







8. CHECK THE REAR STOPLAMP SUPPLY CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

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

3. For 4-door vehicles, measure:





4. For 5-door vehicles, measure:





Is the resistance greater than 10,000 ohms?







9. CHECK THE REAR STOPLAMP SUPPLY CIRCUIT FOR AN OPEN

1. For 4-door vehicles, measure:





2. For 5-door vehicles, measure:





Is the resistance less than 3 ohms?







10. 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?