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 CircuitAir fuel ratio sensor relay
INSPECTION
1. INSPECT AIR FUEL RATIO SENSOR RELAY
Using an ohmmeter, measure the resistance
according to the value(s) in the table below.
Standard resistance
If the result is not as specified, replace the relay. ...
Operation check
1. REMOVE CHECK FUNCTION
Check that the key reminder warning buzzer
sounds.
With the driver side door closed, insert the key
into the ignition key cylinder and then turn the
key to LOCK or ACC.
Check that the buzzer sounds intermittently if
the driver side door ...
Reassembly
1. INSTALL IGNITION OR STARTER SWITCH
ASSEMBLY
(a) Install the ignition or starter switch assembly to the
steering column bracket assembly UPR with the 2
screws.
2. INSTALL KEY INTER LOCK SOLENOID
(a) Install the solenoid to the steering column bracket
assembly with the 2 screws.
3. INSTALL ...