Toyota Tacoma (2015-2018) Service Manual: Air Conditioning Compressor Magnetic Clutch Circuit

Toyota Tacoma (2015-2018) Service Manual / Air Conditioning / Air Conditioning System(for Automatic Air Conditioning System) / Air Conditioning Compressor Magnetic Clutch Circuit

DESCRIPTION

When the air conditioning amplifier assembly is turned on, a magnetic clutch on signal is sent from the MGC terminal of the air conditioning amplifier assembly. Then, the MG CLT relay turns on to operate the magnetic clutch assembly.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

ECM malfunctions can affect the storage of this DTC. Therefore, check all SFI system DTCs and confirm that the system is normal before performing the following inspection (See page ).
Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

(a) Use the Techstream to check if the CAN communication system is functioning normally.

Result

Result	Proceed to
CAN DTC is not output	A
CAN DTC is output	B

GO TO CAN COMMUNICATION SYSTEM

2.	INSPECT MG CLT RELAY

(a) Remove the MG CLT relay.

(b) Inspect the MG CLT relay (See page ).

REPLACE MG CLT RELAY

3.	CHECK HARNESS AND CONNECTOR (MG CLT RELAY - POWER SOURCE CIRCUIT)

(a) Remove the MG CLT relay.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
MG CLT-1 - Body ground	Ignition switch ON	11 to 14 V
MG CLT-5 - Body ground	Ignition switch ON	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CHECK HARNESS AND CONNECTOR (MG CLT RELAY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND MAGNET-CLUTCH ASSEMBLY)

(a) Remove the MG CLT relay.

(b) Disconnect the A35 air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
MG CLT-2 - A35-10 (MGC)	Always	Below 1 Ω
MG CLT-3 - A1-1 (MG+)	Always	Below 1 Ω
MG CLT-2 or A35-10 (MGC) - Body ground	Always	10 kΩ or higher
MG CLT-3 or A1-1 (MG+) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	INSPECT MAGNET-CLUTCH ASSEMBLY

(a) Remove the magnet-clutch assembly (See page (b) Inspect the magnet-clutch assembly (See page ).

(b) Inspect the magnet-clutch assembly (See page ).

REPLACE MAGNET-CLUTCH ASSEMBLY

6.	INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

(a) Reconnect the A35 air conditioning amplifier assembly connector.

(b) Reconnect the A1 magnet-clutch assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A35-10 (MGC) - Body ground	Engine idling "A/C" switch off → on Blower switch: LO Magnet-clutch assembly: off → on	11 to 14 V → Below 1 V

Text in Illustration

*a	Component with harness connected (Air Conditioning Amplifier Assembly)

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

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