Fog/Driving Lamp: Description and Operation

FRONT FOG LAMP

System Description
The front fog lamps are controlled by lighting switch inputs to the BCM (body control module). The lighting switch must be in the 1ST or 2ND position with the high beams OFF before the BCM will request the IPDM E/ R (intelligent power distribution module engine room) to turn the front fog lamps on. The BCM requests the front fog lamps over the CAN communication lines to the IPDM E/R. The CPU (central processing unit) of the IPDM E/R controls the front fog lamp relay coil ground. When energized, the relay directs power to the front fog lamps.

OUTLINE
Power is supplied at all times:
- to front fog lamp relay (located in IPDM E/R),
- to ignition relay (located in IPDM E/R),
- through 15 A fuse (No. 52, located in IPDM E/R) and
- through 20 A fuse (No. 53, located in IPDM E/R)
- to CPU located in IPDM E/R,
- through 40 A fusible link (letter g, located in the fuse and fusible link box)
- to BCM terminal 70,
- through 10 A fuse [No. 8, located in fuse block (J/B)]
- to BCM terminal 57,
- through 10 A fuse [No. 13, located in fuse block (J/B)]
- to combination meter terminal 27.

With the ignition switch in the ON or START position, power is supplied:
- to ignition relay (located in IPDM E/R),
- through 10 A fuse [No. 6, located in fuse block (J/B)]
- to BCM terminal 38. With the ignition switch in the ACC or ON position, power is supplied
- through 10 A fuse [No. 20, located in fuse block (J/B)]
- to BCM terminal 11.

Ground is supplied
- to BCM terminal 67
- through grounds M57 and M61,
- to IPDM E/R terminals 39 and 59
- through grounds E15 and E24.

FOG LAMP OPERATION
The front fog lamp switch is built into the lighting switch. The lighting switch must be in 1ST position or 2ND position and front fog lamp switch must be ON position for front fog lamp operation. The fog lamp will not operate with the high beam headlamps ON.

When the front fog lamp switch is in the ON position, the BCM sends a request, via the CAN communication lines, to the CPU of the IPDM E/R to ground the coil side of the front fog lamp relay. The front fog lamp relay then directs power
- through 15 A fuse (No. 56, located in IPDM E/R)
- through IPDM E/R terminal 50
- to front fog lamp LH terminal 1, and
- through IPDM E/R terminal 51
- to front fog lamp RH terminal 1.

Ground is supplied
- to front fog lamp terminal 2,
- through grounds E15 and E24.
With power and grounds supplied, front fog lamps illuminate.

COMBINATION SWITCH READING FUNCTION
Refer to "System Description" in Body Control Systems.

EXTERIOR LAMP BATTERY SAVER CONTROL
Refer to "System Description".

CAN Communication System Description
Refer to "Information Bus".