Toyota Tacoma (2015-2018) Service Manual: Back-up Power Source Circuit

Toyota Tacoma (2015-2018) Service Manual / Air Conditioning / Air Conditioning System(for Automatic Air Conditioning System) / Back-up Power Source Circuit

DESCRIPTION

The back-up power source circuit for the air conditioning amplifier assembly is shown below. Power is supplied even when the ignition switch is off. The power is used for diagnostic trouble code memory, etc.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY)

(a) Disconnect the A36 air conditioning amplifier assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A36-17 (B) - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BODY GROUND)

(a) Disconnect the A36 air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
A36-10 (GND) - Body ground	Always	Below 1 Ω

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPAIR OR REPLACE HARNESS OR CONNECTOR

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