Power Supply And Ground Circuit For Auto Amp

POWER SUPPLY AND GROUND CIRCUIT FOR AUTO AMP.





Description

COMPONENT DESCRIPTION

Unified Meter and A/C Amp. (Automatic Amplifier)





The unified meter and A/C amp. (1) has a built-in microcomputer which processes information sent from various sensors needed for air conditioner operation. The air mix door motor(s), mode door motor, intake door motor, blower motor and compressor are then controlled.
When the various switches and temperature control dial are operated, data is input to the unified meter and A/C amp. from the AV control unit using CAN communication.
Self-diagnosis functions are also built into unified meter and A/C amp. to provide quick check of malfunctions in the auto air conditioner system.




Component Function Check
1.CONFIRM SYMPTOM BY PERFORMING THE FOLLOWING OPERATIONAL CHECK
1. Press AUTO switch.
2. Display should indicate AUTO. Confirm that the compressor clutch engages (sound or visual inspection).
(Discharge air and blower speed depend on ambient, in-vehicle and set temperatures.)
Does magnet clutch engaged?
YES - END.
NO - Go to Diagnosis Procedure. SEE Diagnosis Procedure.




Diagnosis Procedure
1.CHECK POWER SUPPLY CIRCUIT FOR UNIFIED METER AND A/C AMP.
1. Disconnect unified meter and A/C amp. connector.
2. Check voltage between unified meter and A/C amp. harness connector and ground.





Is the inspection result normal?
YES - GO TO 3.
NO - GO TO 2.
2.CHECK FUSE
Check 10A fuses [Nos. 3, 11 and 19, located in the fuse block (J/B)]. Fuse Block - Junction Box (J/B), "Fuse, Connector and
Terminal Arrangement".
Is the inspection result normal?
YES - Check harness for open circuit. Repair or replace if necessary.
NO - Check harness for short circuit and replace fuse.
3.CHECK GROUND CIRCUIT FOR UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Check continuity between unified meter and A/C amp. harness connector and ground.





Is the inspection result normal?
YES - GO TO 4.
NO - Repair harness or connector.
4.CHECK PRESET SWITCH
Check preset switch. Symptom Table Base Audio Without Navigation (BASE AUDIO WITHOUT NAVIGATION), Symptom Table Bose Audio Without Navigation, Symptom Table Bose Audio With Navigation (BOSE AUDIO WITH
NAVIGATION).
Is the inspection result normal?
YES - Replace unified meter and A/C amp.
NO - Repair or replace malfunctioning part(s).