Fog/Driving Lamp: Description and Operation

FRONT FOG LAMP

System Description
The control of the front fog lamps is dependent upon the position of the lighting switch. The lighting switch must be in the 2ND position or AUTO position (headlamp is ON) for front fog lamp operation. When the lighting switch is placed in front fog lamp switch ON position the BCM (body control module) receives input signal requesting the front fog lamps to illuminate. When the headlamps are illuminated, this input signal is communicated to the IPDM E/R (intelligent power distribution module engine room) through the CAN communication lines. The CPU (central processing unit) located in the IPDM E/R controls the front fog lamp relay. When activated, this relay directs power to the front fog lamps.

OUTLINE
Power is supplied at all times
- to ignition relay, located in IPDM E/R, from battery direct,
- through 15 A fuse (No. 88, located in IPDM E/R)
- to front fog lamp relay, located in IPDM E/R,
- through 15 A fuse (No. 78, located in IPDM E/R)
- to CPU located in IPDM E/R,
- through 10 A fuse (No. 71, located in IPDM E/R)
- to CPU located in IPDM E/R,
- through 50 A fusible link (letter F, located in fuse, fusible link and relay box)
- to BCM terminal 55,
- through 10 A fuse [No. 18, located in fuse block (J/B)]
- to BCM terminal 42.

With the ignition switch in the ON or START position, power is supplied
- to ignition relay, located in IPDM E/R, from battery direct,
- through ignition relay, located in IPDM E/R
- to CPU located in IPDM E/R,
- through 10 A fuse [No. 1, 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. 6, located in fuse block (J/B)]
- to BCM terminal 11.

Ground is supplied
- to BCM terminal 52
- through grounds M30 and M66,
- to IPDM E/R terminals 38 and 60
- through grounds E17 and E43.

FRONT FOG LAMP OPERATION
The front fog lamp switch is built in lighting switch. The lighting switch must be in 2ND position or AUTO position (headlamp is ON) and front fog lamp switch must be ON position for front fog lamp operation.

With the front fog lamp switch in the ON position, the CPU located in the IPDM E/R grounds coil side of the front fog lamp relay. Front fog lamp relay then directs power
- through IPDM E/R terminal 37
- to front combination lamp LH terminal 1,
- through IPDM E/R terminal 36
- to front combination lamp RH terminal 1.

Ground is supplied
- to front combination lamp RH and LH terminals 8
- through grounds E17 and E43.

With power and grounds supplied, front fog lamps illuminate.

COMBINATION SWITCH READING FUNCTION
Refer to BCS-3, "COMBINATION SWITCH READING FUNCTION".

EXTERIOR LAMP BATTERY SAVER CONTROL
When lighting switch is in the 2ND position and ignition switch is turned from ON or ACC to OFF, the battery saver control feature is activated.
Under this condition, front fog lamps (and headlamps) remain illuminated for 5 minutes, then front fog lamps (and headlamps) are turned off.
Exterior lamp battery saver control mode can be changed by the function setting of CONSULT-II.

CAN Communication System Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.

CAN Communication Unit
Refer to Information Bus. CAN System Specification Chart