PINPOINT TEST AJ : The Trailer Parking Lamps Are Inoperative
NOTE:
Before beginning diagnostics, visually inspect the trailer tow connector for signs of corrosion or damage. Repair or install a new trailer tow connector as required.
- AJ1 CHECK FOR VOLTAGE THROUGH THE TRAILER TOW CONNECTOR
- Ignition OFF.
- Place the headlamp switch in the parking lamps on position.
- For the 4-pin connector, measure:
Positive Lead Measurement / Action Negative Lead C439-3 Ground
- For the 7-pin connector, measure:
Positive Lead Measurement / Action Negative Lead Trailer Tow Connector Pin 6 Ground
Is the voltage greater than 11 volts?
Yes The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility. No For the 4-pin connector, GO to AJ3. For the 7-pin connector, GO to AJ2. - AJ2 CHECK FOR VOLTAGE TO THE TRAILER TOW CONNECTOR (7-PIN)
- Disconnect: Trailer Tow Connector.
- Measure:
Positive Lead Measurement / Action Negative Lead C4099-6 Ground
Is the voltage greater than 11 volts?
Yes INSTALL a new trailer tow connector. TEST the system for normal operation. No GO to AJ3. - AJ3 CHECK THE TRAILER TOW PARKING LAMP RELAY
- Place the headlamp switch in the off position.
- Disconnect: Trailer Tow Parking Lamp Relay.
- Substitute a known good relay.
- Place the headlamp switch in the parking lamps on position.
- For the 4-pin connector, measure:
Positive Lead Measurement / Action Negative Lead C439-3 Ground
- For the 7-pin connector, measure:
Positive Lead Measurement / Action Negative Lead C4099-6 Ground
Is the voltage greater than 11 volts?
Yes REMOVE the known good relay. INSTALL a new trailer tow parking lamp relay. No REMOVE the known good relay. GO to AJ4. - AJ4 CHECK THE TRAILER TOW PARKING LAMP RELAY COIL VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Measure:
Positive Lead Measurement / Action Negative Lead Trailer Tow Right Stop/Turn Relay Pin 2 Ground
Is the voltage greater than 11 volts?
Yes GO to AJ5. No REPAIR the circuit. - Measure:
- AJ5 CHECK THE TRAILER TOW PARKING LAMP RELAY BJB VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Place the headlamp switch in the off position.
- Measure:
Positive Lead Measurement / Action Negative Lead Trailer Tow Right Stop/Turn Relay Pin 3 Ground
Is the voltage greater than 11 volts?
Yes GO to AJ6. No VERIFY the BJB fuse 84 (20A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short - AJ6 CHECK THE TRAILER TOW PARKING LAMP RELAY GROUND CIRCUIT FOR AN OPEN
- Measure:
Positive Lead Measurement / Action Negative Lead Trailer Tow Right Stop/Turn Relay Pin 3 Trailer Tow Right Stop/Turn Relay Pin 1
Is the voltage greater than 11 volts?
Yes REPAIR the trailer tow parking lamp relay output circuit to the trailer tow connector for an open. No REPAIR the trailer tow parking lamp relay ground circuit for an open. - Measure:
