Diagnostic Test

Turn the ignition on.

With the Scan Tool, clear all TIPM DTC's.

Turn the Stop Lamps on.

With the scan tool, read the DTC information.

Does the Scan Tool read: B1785-STOP LAMP CONTROL CIRCUIT HIGH? 

Yes 

1. Go to Step 2.

No 

1. The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
2. Perform the BODY VERIFICATION TEST - VER 1 .

Turn the ignition off.

Inspect the Left and Right Stop Lamp Bulb Assemblies.

Are the inoperative bulbs OK? 

Yes 

1. Go to Step 3.

No 

1. Replace the Inoperative bulb or bulbs in accordance with the service information.
2. Perform the BODY VERIFICATION TEST - VER 1 .

Turn the ignition off.

Disconnect the TIPM C3 harness connector.

Disconnect the Left and Right Stop Lamp harness connectors.

Measure the resistance of the (L55) Stop Lamp Control circuit.

Is the resistance above 5.0 ohms? 

Yes 

1. Repair the (L55) Stop Lamp Control circuit for an open condition.
2. Perform the BODY VERIFICATION TEST - VER 1 .

No 

1. Go to Step 4.

Turn the ignition off.

Disconnect the TIPM C3 harness connector.

Disconnect the Left and Right Stop Lamp harness connectors.

Turn the ignition on.

Measure for voltage on the (L55) Stop Lamp Control circuit.

Is the voltage above 10.0 volts? 

Yes 

1. Repair the (L55) Stop Lamp Control circuit for a short to voltage condition.
2. Perform the BODY VERIFICATION TEST - VER 1 .

No 

1. Replace the Totally Integrated Power Module (TIPM) in accordance with the service information.
2. Perform the BODY VERIFICATION TEST - VER 1 .