Test B: The Daytime Running Lamps Are On With the Ignition Switch Off

PINPOINT TEST B: THE DAYTIME RUNNING LAMPS ARE ON WITH THE IGNITION SWITCH OFF

Test B1-B5:

Test B6-B7:

Normal Operation
Battery voltage is supplied to the daytime running lamp (DRL) enable relay through circuit 2017 (WH/RD). Switched power from circuit 295 (LB/PK) supplies power to the DRL enable relay coil. Ground for the DRL enable relay is provided through circuit 57 (BK). When the DRL enable relay is energized, voltage is routed through circuit 1731 (RD/BK) to the DRL relay which is then routed to circuit 471 (OG/LG). Circuit 471 (OG/LG) carries the voltage to the DRL resistor. Voltage is reduced as it passes through the DRL resistor. Reduced voltage that passes through the DRL resistor flows through circuit 13 (RD/BK) to the central junction box (CJB) and then on to the low beam headlamps. The DRL relay coil receives voltage from circuit 12 (LG/BK) when the high beams are illuminated, which interrupts the voltage to the DRL resistor. The DRL relay is provided ground through circuit 57 (BK).

Possible Causes
- Circuit 295 (LB/PK) short to power
- Circuit 471 (OG/LG) short to power
- Circuit 1731 (RD/BK) short to power
- DRL enable relay
- Ignition switch
- Central junction box (CJB)