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 CircuitHeater relay (for rear air conditioning system)
ON-VEHICLE INSPECTION
1. INSPECT REAR HEATER RELAY
(a) Remove the rear heater relay.
(b) Measure the resistance according to the value(s) in
the table below.
Standard resistance
If the resistance is not as specified, replace the rear
heater relay. ...
Disassembly
1. Remove park/neutral position switch assembly
(A) remove the nut, washer and control shaft lever.
(B) using a screwdriver, unstake the nut stopper, and
remove the lock nut and nut stopper.
(c) Remove the 2 bolts and pull out the park/neutral
position switch.
2. REMOVE BREATHER PLUG H ...