Fog/Driving Lamp: Description and Operation

FRONT FOG LAMP

System Description
Control of the front 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 (headlamp is ON) for front fog lamp operation. When the lighting switch is placed in the front fog lamp 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 coil. 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 M, located in fuse, fusible link and relay box)
- to BCM terminal 55,
- through 15 A fuse [No. 22, located in fuse block (J/B)]
- to BCM terminal 42.

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

When ignition switch is in 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 terminals 49 and 52
- through grounds M35, M45 and M85,
- to IPDM E/R terminals 38 and 60
- through grounds E21, E50 and E51.

FRONT FOG LAMP OPERATION
The front fog lamp switch is built into combination switch. The lighting switch must be in the 2ND position or AUTO position (headlamp is ON) and the front fog lamp switch must be ON for front fog lamp operation. With the front fog lamp switch in the ON position, the CPU located in the IPDM E/R grounds the coil side of the front fog lamp relay. The front fog lamp relay then directs power
- through IPDM E/R terminal 36
- to front fog lamp RH terminal 1,
- through IPDM E/R terminal 37
- to front fog lamp LH terminal 1.

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

With power and grounds supplied, front fog lamps illuminate.

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

EXTERIOR LAMP BATTERY SAVER CONTROL
When the combination switch (lighting switch) is in the 2ND position (ON), the front 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 front fog lamps (and headlamps) remain illuminated for 5 minutes, then the 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