Back-up Power Source Circuit

DESCRIPTION

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

WIRING DIAGRAM

INSPECTION PROCEDURE

1. INSPECT ECU-B NO.1 FUSE

1. Remove the ECU-B No.1 fuse from the fusible link block.

2. Measure the resistance according to the value(s) in the table below.
   

   Resistance:

   Tester item	Condition	Specified condition
   ECU-B No.1 fuse	Always	Below 1 Ω

NG	REPLACE ECU-B NO.1 FUSE

OK

2. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

1. Remove the A/C amplifier assembly with the connectors still connected.

2. Measure the voltage according to the value(s) in the table below.

   Voltage:

   Tester connection (Symbols)	Condition	Specified condition
   A11-2 (B) - A11-6 (GND)	Always	10 to 14 V

NG	Go to step 3

OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

3. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER ASSEMBLY - BODY GROUND)

1. Disconnect the connector from the A/C amplifier assembly.

2. Measure the voltage according to the value(s) in the table below.

   Voltage:

   Tester connection (Symbols)	Condition	Specified condition
   A11-2 (B) - Body ground	Always	10 to 14 V

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER ASSEMBLY - BODY GROUND)

1. Measure the resistance according to the value(s) in the table below.

   Resistance:

   Tester connection (Symbols)	Condition	Specified condition
   A11-6 (GND) - Body ground	Always	Below 1 Ω

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY