DESCRIPTION
This is the back-up power source for the A/C amplifier. Power is supplied even when the ignition switch is off and is used for diagnostic trouble code memory, etc.
WIRING DIAGRAM

INSPECTION PROCEDURE
1 INSPECT FUSE (ECU-B)
(a) Remove the ECU-B fuse from the engine room junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance


2 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)

(a) Disconnect the connector from the A/C amplifier.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage


PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
ACC Power Source CircuitOn-vehicle inspection
1. INSPECT FOR FUEL PUMP OPERATION AND FUEL
LEAK
(a) Check fuel pump operation.
(1) Connect the intelligent tester to the DLC3.
(2) Turn the engine switch on (IG) and push the
intelligent tester main switch on.
NOTICE:
Do not start the engine.
(3) Select the following menu it ...
On-vehicle inspection
1. Check battery electrolyte level
(a) Check the electrolyte level.
(1) If the electrolyte level is low, replace the battery
(or add distilled water) and check the charging
system.
2. CHECK BATTERY SPECIFIC GRAVITY
(a) Check the color of the hydrometer.
Result
3. CHECK BATTERY VOLTAGE ...
Sensor detection display, obstacle distance
Distance display
Sensors that detect an obstacle will illuminate continuously or blink.
*1: The images may differ from that shown in the illustrations.
*2: Multi-information display
*3: Audio system screen
Buzzer operation and distance to an obstacle
A buzzer sounds when the sensors are o ...