Toyota Tacoma (2015-2018) Service Manual: Compressor Lock Sensor Circuit (B1422)

Toyota Tacoma (2015-2018) Service Manual / Air Conditioning / Air Conditioning System(for Manual Air Conditioning System) / Compressor Lock Sensor Circuit (B1422)

SYSTEM DESCRIPTION

The ECM sends the engine speed signal to the air conditioning amplifier assembly via CAN communication.

The air conditioning amplifier assembly reads the difference between compressor speed and engine speed. When the difference becomes too large, the air conditioning amplifier assembly determines that the compressor is locked, and turns the magnet-clutch assembly off.

DTC No.	DTC Detection Condition	Trouble Area
B1422	Open or short in A/C lock sensor circuit	Magnet-clutch assembly A/C lock sensor Harness or connector Air conditioning amplifier assembly CAN communication system

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.
- for 2TR-FE (See page )
- for 2GR-FKS (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 A/C LOCK SENSOR

(a) Remove the A/C lock sensor (See page (b) Inspect the A/C lock sensor (See page ). ).

(b) Inspect the A/C lock sensor (See page ).

REPLACE A/C LOCK SENSOR

3.	CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - COOLER COMPRESSOR ASSEMBLY)

(a) Disconnect the A1 cooler compressor assembly connector.

(b) Disconnect the A14 air conditioning amplifier assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
A14-4 (LOCK) - A1-2	Always	Below 1 Ω
A14-33 (SG-1) - A1-3	Always	Below 1 Ω
A14-4 (LOCK) or A1-2 - Body ground	Always	10 kΩ or higher
A14-33 (SG-1) or A1-3 - Body ground	Always	10 kΩ or higher

Result	Proceed to
NG	A
OK (When troubleshooting according to Problem Symptoms Table)	B
OK (When troubleshooting according to the DTC)	C

REPAIR OR REPLACE HARNESS OR CONNECTOR

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

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