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Fog/Driving Lamp: Description and Operation

System Description
Control of the fog lamps is dependent upon the position of the combination switch (lighting switch). The lighting switch must be in the 2ND position or AUTO position (LOW beam is ON) for front fog lamp operation.When the lighting switch is placed in the fog lamp position the BCM (body control module) receives input signal requesting the 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) across the CAN communication lines. The central processing unit of the IPDM E/R controls the front fog lamp relay coil. When activated, this relay directs power to the front fog lamps.

OUTLINE
Power is supplied at all times
- through 15 A fuse [No. 88, located in the IPDM E/R (intelligent power distribution module engine room)]
- to front fog lamp relay, located in the IPDM E/R (intelligent power distribution module engine room)
- through 15 A fuse [No. 78, located in the IPDM E/R (intelligent power distribution module engine room)]
- to CPU (central processing unit) in the IPDM E/R (intelligent power distribution module engine room)
- through 10 A fuse [No. 71, located in the IPDM E/R (intelligent power distribution module engine room)]
- to CPU (central processing unit) in the IPDM E/R (intelligent power distribution module engine room).

Power is also supplied at all times
- through 50 A fusible link (letter M, located in the fuse and fusible link box)
- to BCM (body control module) terminal 55
- through 15 A fuse [No. 22, located in the fuse block (J/B)]
- to BCM (body control module) terminal 42.

When the ignition switch is in ON or START position, power is supplied
- through 15 A fuse [No. 1 located in the fuse block (J/B)]
- to BCM (body control module) terminal 38.

When the ignition switch is in ACC or ON position, power is supplied
- through 10 A fuse [No. 6, located in the fuse block (J/B)]
- to BCM (body control module) terminal 11.

Ground is supplied
- to BCM (body control module) terminals 49 and 52
- through grounds M35, M45 and M85
- to IPDM E/R (intelligent power distribution module engine room) terminals 38 and 60
- through grounds E21, E50 and E51.

Fog Lamp Operation
The fog lamp switch is built into the combination switch. The lighting switch must be in the 2ND position or AUTO position (LOW beam is ON) and the fog lamp switch must be ON for fog lamp operation.

With the fog lamp switch in the ON position, the CPU (central processing unit) of the IPDM E/R (intelligent power distribution module engine room) grounds the coil side of the fog lamp relay. The fog lamp relay then directs power
- through IPDM E/R terminal 37
- to front fog lamp LH terminal 1
- through IPDM E/R terminal 36
- to front fog lamp RH terminal 1.

Ground is supplied
- to front fog lamp LH terminal 2
- through grounds E21, E50 and E51, and
- to front fog lamp RH terminal 2
- through grounds E21, E50 and E51.

With power and grounds supplied, the front fog lamps illuminate.

COMBINATION SWITCH READING FUNCTION
Refer to "COMBINATION SWITCH READING FUNCTION". Body Control Module

EXTERIOR LAMP BATTERY SAVER CONTROL
When the combination switch (lighting switch) is in the 2ND position (ON), the fog lamp switch is ON, and the ignition switch is turned from ON or ACC to OFF, the battery saver control feature is activated.

Under this condition, the fog lamps (and headlamps) remain illuminated for 5 minutes, then the 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".