Test Q: The Fog Lamps Are Inoperative

PINPOINT TEST Q: THE FOG LAMPS ARE INOPERATIVE

Normal Operation
The smart junction box (SJB) sends a reference signal to the headlamp switch through circuit CLF21 (GY/VT). When the fog lamp switch is engaged, the voltage signal is routed to ground.

Voltage is supplied to the switched side of the fog lamp relay from the battery junction box (BJB) fuse 31 (15A) through circuit SBB31 (WH/RD).

When the SJB detects the fog lamp on request, the SJB provides a voltage to the fog lamp relay coil through circuit CLF28 (BN/WH). The fog lamp relay coil ground is provided through circuit GD120 (BK/GN). When the fog lamp relay is energized, voltage is routed through circuit CLF12 (BN/YE) to the fog lamps. The fog lamps share a common ground through circuit GD123 (BK/GY).

- DTC B2030 (Front Fog Lamp Relay Ckt Failure) - is a continuous and on-demand DTC that sets when the SJB detects a short to ground from the fog lamp relay coil ground controlled circuit. The self-test must be run after the repair in order for the SJB to enable the output for the fog lamp voltage supply.
- DTC B2512 (Front Fog Lamp Relay Ckt Short to Battery) - is a continuous and on-demand DTC that sets when the SJB detects an open from the fog lamp relay coil voltage supply circuit.

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Fog lamp relay
- Headlamp switch
- SJB

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Q7-Q8:

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Q10-Q12:

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