Pinpoint Test Z: The Trailer Lamps Are On Continuously
WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
- Z1 CHECK THE CIRCUITRY FOR SHORTS TO VOLTAGE
- Key in OFF position.
- Disconnect: Trailer Tow C439.
- Key in ON position.
- Measure the voltage between the trailer tow C439, harness side and ground as follows:TRAILER TOW CONNECTOR-PIN REFERENCE
Connector-Pin Circuit C439-1 64 (DG) C439-2 52 (YE) C439-3 962 (BN/WH) - Is any voltage present?
Yes: GO to Z2.
No: The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair center.
- Z2 CHECK THE SJB
- Key in OFF position.
- Disconnect: SJB C2280c.
- Key in ON position.
- Measure the voltage between the trailer tow C439, harness side and ground as follows:TRAILER TOW CONNECTOR-PIN REFERENCE
Connector-Pin Circuit C439-1 64 (DG) C439-2 52 (YE) C439-3 962 (BN/WH) - Is any voltage present?
Yes: REPAIR the circuit in question. TEST the system for normal operation.
No: GO to Z3.
- Z3 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
- corrosion
- pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes: INSTALL a new SJB. REFER to SMART JUNCTION BOX (SJB) . TEST the system for normal operation.
No: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.