Purpose
The auto light sensor detects the illumination level above and in front of the vehicle and outputs it to the front body control module (FBCM).
Function
The auto-light sensor uses the upward illumination level sensor to detect the illumination level above the vehicle, and uses the forward illumination level sensor to detect the illumination level in front of the vehicle.
Illumination level adjustment function
The illumination level can be switched through 5 levels by using the Mazda Modular Diagnostic System (M-MDS) or the audio unit (with color LCD)..
On-board diagnostic function
If there is a malfunction in the auto light sensor, notifies the front body control module (FBCM) and detects a DTC from the front body control module (FBCM).
For details on DTCs, refer to the diagnostic system (front body control module (FBCM)), DTC table (front body control module (FBCM)) in the Workshop Manual.
Construction
The auto-light sensor is integrated with the rain sensor as a single unit.
The auto light sensor consists of lens, forward illumination level sensor (photodiode), upward illumination level sensor (photodiode), and microcomputer.

Operation
CAUTION:
Correct illumination level detection is not be possible under the following conditions and could cause the system to operate incorrectly.
Stickers or labels are attached to the auto-light sensor area on the windshield.
Dirt is adhering to the the auto-light sensor area on the windshield.
1. The auto light sensor detects the illumination level above and in front of the vehicle when the ignition is switched ON and the light switch is operated to the AUTO position.
2. The auto light sensor outputs a headlight (LO) on signal to the front body control module (FBCM) according to the detected illumination level.
Fail-safe
Function not equipped.
Adaptive Front Lighting System (Afs) Off Switch Inspection
Back Up Light Switch InspectionAwd Solenoid Inspection
1. Disconnect the negative battery cable.
2. Disconnect the AWD solenoid connector.
3. Measure resistance between AWD solenoid connector terminals A and B.
If the resistance is not within the specification, replace the coupling unit.
AWD solenoid resistance
2.2—2.7 oh ...
Filament Inspection
1. Switch the ignition ON (engine off).
2. Turn the rear window defroster switch on.
CAUTION:
Directly touching the rear window defroster filament with the lead of the
tester could damage it. Wrap aluminum foil around the end of the lead and inspect
the filament by touching it ...
Magnetic Clutch Adjustment [Full Auto Air Conditioner]
1. Measure the clearance around the entire circumference between the pressure
plate and A/C compressor pulley using a thickness gauge.
2. Verify the clearance.
If not within the specification, remove the pressure plate and adjust the
clearance by changing the shim (0.2 mm {0.008 i ...