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Test W: The Reversing Lamps Are On Continuously

PINPOINT TEST W: THE REVERSING LAMPS ARE ON CONTINUOUSLY


W1-W5:






Normal Operation
Voltage is supplied from the battery junction box (BJB) fuse 33 (20A) to the switched side of the reversing lamps relay. The reversing lamps relay coil power is supplied by the transmission control module (TCM) (also called a main control valve body for Expedition and a mechatronic assembly for Navigator) through circuit CAT03 (GY/BN). The reversing lamps relay coil ground is controlled by the TCM through circuit RET24 (BN/BU). When the reversing lamps relay is energized, voltage is routed to the reversing lamps, the interior rear view mirror, and BJB fuse 63 (15A) (trailer tow reversing lamps) through circuit CLS10 (GN/BN). Voltage from the BJB fuse 63 (15A) is then routed to the trailer tow connector through circuit CAT16 (GY/BN).

Possible Causes
- Circuit CAT16 (GY/BN) short to voltage
- Circuit CLS10 (GN/BN) short to voltage
- Reversing lamps relay
- Rear view mirror
- TCM