System Diagram

System Description
Control of the headlamp system operation is dependent upon the position of the combination switch (lighting and turn signal switch). When the lighting switch is placed in the 2nd position, the BCM (body control module) receives input requesting the headlamps and park lamps to illuminate. This input is communicated to the IPDM E/R (intelligent power distribution module engine room) across the CAN communication lines. The CPU (central processing unit) of the IPDM E/R controls the headlamp high and headlamp low relay coils. When energized, these relays direct power to the respective headlamps, which then illuminate.
Component Parts Location

Component Description
LOW BEAM OPERATION
When the lighting switch is in 2ND position, the BCM receives input requesting the headlamps to illuminate.
This input is communicated to the IPDM E/R across the CAN communication lines. The CPU of the IPDM E/R controls the headlamp low relay coil which supplies power to the low beam headlamps.
HIGH BEAM OPERATION/FLASH-TO-PASS OPERATION
With the lighting switch in the 2ND position and placed in HIGH position, the BCM receives input requesting the headlamp high beams to illuminate. The flash-to-pass feature can be used any time and also sends a signal to the BCM. This input is communicated to the IPDM E/R across the CAN communication lines. The CPU of the combination meter controls the ON/OFF status off the HIGH BEAM indicator. The CPU of the IPDM E/R controls the headlamp high relay coil which supplies power to the high beam headlamps.
The combination meter receives a high beam request signal (ON) through the CAN communication lines and turns the high beam indicator lamp ON.
EXTERIOR LAMP BATTERY SAVER CONTROL
With the lighting switch (combination switch) in the 2nd position and the ignition switch is turned from ON or ACC to OFF, the battery saver feature is activated.
Under this condition, the headlamps remain illuminated for 5 minutes unless the lighting switch position is changed. If the lighting switch position is changed, then the headlamps are turned off.
This setting can be changed by CONSULT. Refer to EXL-193, "BATTERY SAVER : CONSULT Function (BCM - BATTERY SAVER)".
Daytime running light systemMain line between HVAC and A-bag circuit
Diagnosis Procedure
1.CHECK HARNESS CONTINUITY (OPEN CIRCUIT)
Turn the ignition switch OFF.
Disconnect the battery cable from the negative terminal.
Disconnect the following harness connectors.
A/C auto amp.
Harness connectors M1 and E30
Check the continuity between the A/C au ...
Exhaust gas (carbon monoxide)
WARNING
Do not breathe exhaust gases; they
contain colorless and odorless carbon
monoxide. Carbon monoxide is dangerous.
It can cause unconsciousness or
death.
If you suspect that exhaust fumes are
entering the vehicle, drive with all windows
fully open, and have the vehicle
in ...
P1778 step motor
Description
The step motor changes the step by turning 4
coils ON/OFF according to the signal from TCM. As a result,
the flow of line pressure to primary pulley is changed and pulley ratio is
controlled.
This diagnosis item is detected when the
electrical syste ...