Diagnostic Routine R
Diagnostic Routine R
Diagnostic Overview
One Turn Signal Lamp Is Inoperative Or Always On
Refer to Wiring Diagram Set 90 for schematic and connector information Electrical Diagrams.
Normal Operation and Fault Conditions
REFER to Turn Signals .
BCM (Body Control Module) DTC Fault Trigger Conditions
DDM (Driver Door Module)/ PDM (Passenger Door Module) DTC Fault Trigger Conditions
Visual Inspection and Diagnostic Pre-checks
- Inspect the turn lamp bulb and make sure it is OK.
- Inspect the headlamp assembly, exterior rear view mirror or rear lamp assembly for damage.
Pinpoint Test
1. DETERMINE IF A TURN LAMP IS ALWAYS ON
1. Ignition ON.
2. NOTE: If a rear turn lamp and mirror turn lamp are both inoperative for vehicles without door modules (window one-touch up), follow the diagnostics for the rear turn lamp.
Observe the turn lamps.
Is any turn lamp illuminated?
2. CHECK THE FRONT TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
1. Ignition OFF.
2. Disconnect:
3. Ignition ON.
Does the turn lamp continue to illuminate?
3. CHECK FOR VOLTAGE TO THE FRONT TURN LAMP
1. Ignition OFF.
2. Disconnect: Left or Right Headlamp.
3. Ignition ON.
4. Activate the hazard flasher lamp function.
5. Measure:
Does the voltage alternate from 0 to greater than 11 volts?
4. CHECK THE HEADLAMP GROUND CIRCUIT FOR AN OPEN
1. Measure:
Does the voltage alternate from 0 to greater than 11 volts?
5. CHECK THE FRONT TURN LAMP SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. Ignition OFF.
2. Deactivate the hazard flasher lamp function.
3. Disconnect: BCM (Body Control Module) C2280D (left front turn lamp).
4. Disconnect: BCM (Body Control Module) C2280A (right front turn lamp).
5. Measure:
Is the resistance greater than 10,000 ohms?
6. CHECK THE FRONT TURN LAMP SUPPLY CIRCUIT FOR AN OPEN
1. For the left front turn lamp, measure:
2. For the right front turn lamp, measure:
Is the resistance less than 3 ohms?
7. CHECK FOR VOLTAGE TO THE REAR TURN LAMP
1. Ignition OFF.
2. Disconnect: Left or Right Rear Lamp.
3. Ignition ON.
4. Activate the hazard flasher lamp function.
5. For 4-door vehicles, measure:
6. For 5-door vehicles, measure:
Does the voltage alternate from 0 to greater than 11 volts?
8. CHECK THE REAR LAMP GROUND CIRCUIT FOR AN OPEN
1. For 4-door vehicles, measure:
2. For 5-door vehicles, measure:
Does the voltage alternate from 0 to greater than 11 volts?
9. ISOLATE THE EXTERIOR MIRROR
1. Ignition OFF.
2. Deactivate the hazard flasher lamp function.
3. Disconnect: Suspect Exterior Mirror.
4. Ignition ON.
5. Activate the hazard flasher lamp function.
Does the rear turn lamp in question operate?
10. CHECK THE REAR TURN LAMP SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. Ignition OFF.
2. Deactivate the hazard flasher lamp function.
3. Disconnect: BCM (Body Control Module) C2280B.
4. For 4-door vehicles, measure:
5. For 5-door vehicles, measure:
Is the resistance greater than 10,000 ohms?
11. CHECK THE REAR TURN LAMP SUPPLY CIRCUIT FOR AN OPEN
1. For 4-door vehicles, measure:
2. For 5-door vehicles, measure:
Is the resistance less than 3 ohms?
12. CHECK THE EXTERIOR MIRROR TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
1. Ignition OFF.
2. Disconnect: Left or Right Exterior Mirror.
3. Ignition ON.
4. Activate the hazard flasher lamp function.
5. Measure:
Does the voltage alternate from 0 to greater than 11 volts?
13. CHECK THE EXTERIOR MIRROR TURN LAMP GROUND CIRCUIT FOR AN OPEN
1. Measure:
Does the voltage alternate from 0 to greater than 11 volts?
14. CHECK FOR VOLTAGE TO THE EXTERIOR MIRROR
1. Ignition OFF.
2. Disconnect: Left or Right Exterior Mirror.
3. Ignition ON.
4. Activate the hazard flasher lamp function.
5. Measure:
Does the voltage alternate from 0 to greater than 11 volts?
15. CHECK THE EXTERIOR MIRROR GROUND CIRCUIT INTEGRITY
1. Measure:
Does the voltage alternate from 0 to greater than 11 volts?
16. CHECK THE EXTERIOR MIRROR GROUND CIRCUIT FOR AN OPEN
1. Ignition OFF.
2. Deactivate the hazard flasher lamp function.
3. Disconnect: DDM (Driver Door Module) C501B (left mirror).
4. Disconnect: PDM (Passenger Door Module) C652B (right mirror).
5. Measure:
Is the resistance less than 3 ohms?
17. CHECK THE EXTERIOR MIRROR TURN LAMP SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. Ignition OFF.
2. Deactivate the hazard flasher lamp function.
3. Disconnect: DDM (Driver Door Module) C501B (left mirror).
4. Disconnect: PDM (Passenger Door Module) C652B (right mirror).
5. Measure:
Is the resistance greater than 10,000 ohms?
18. CHECK THE MIRROR TURN LAMP SUPPLY CIRCUIT FOR AN OPEN
1. Measure:
Is the resistance less than 3 ohms?
19. 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?
