Tests AB

PINPOINT TEST AB: THE TRAILER LAMPS ARE ON CONTINUOUSLY

Test AB1-AB2:

Test AB2 Continued:

Normal Operation
Circuit 30S-ND5 (RD/BU) is spliced and voltage is carried to the trailer tow auxiliary junction box (AJB) through circuits 30S-DC1 (RD/BU) and 30S-DC4 (RD/BU). After passing through two fuses (one for each circuit), voltage from the trailer tow AJB is then carried to the trailer tow module through circuits 30S-ND16A (RD/BU) and 30S-ND16B (RD/BU). Input for the parking lamps to the trailer tow module is through circuit 31S-ND21 (BK/OG). Input for the LH stop/turn lamp to the trailer tow module is through circuit 31S-ND19 (BK/BU). Input for the RH stop/turn lamp to the trailer tow module is through circuit 31S-ND18 (BK/YE). Based on the signals received from the inputs, the trailer tow module will supply voltage to the trailer tow connector through circuits 87-ND29 (BN/BU) (parking lamps), 88-ND28 (YE) (LH stop/turn lamp) and 96-ND31 (GN/BU) (RH stop/turn lamp).

Possible Causes
- circuit 87-ND29 (BN/BU) short to power
- circuit 88-ND28 (YE) short to power
- circuit 96-ND31 (GN/BU) short to power
- trailer tow module
- trailer