Toyota Tundra Service Manual: ECU Power Source Circuit

DESCRIPTION

This circuit provides power to operate the air conditioning amplifier.

WIRING DIAGRAM

PROCEDURE

1.	INSPECT FUSE (ECU-B NO.2)

(a) Remove the ECU-B NO.2 fuse from the driver side junction block.

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

Standard resistance:

Tester Connection	Condition	Specified Condition
ECU-B NO.2 fuse	Always	Below 1 Ω

REPLACE FUSE

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

(a) Disconnect the J19 air conditioning amplifier connector.

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

Standard resistance:

Tester Connection	Condition	Specified Condition
J19-14 (GND) - Body ground	Always	Below 1 Ω

Standard voltage:

Tester Connection	Condition	Specified Condition
J19-21 (B) - Body ground	Always	11 to 14 V

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

REPAIR OR REPLACE HARNESS OR CONNECTOR

Toyota Tundra Service Manual > Lane Departure Alert System: Lost Communication with Yaw Rate Sensor Module (U0123,U0126,U0129,U0142,U0155)
DESCRIPTION These DTCs are output when a communication malfunction occurs between the sensors and ECUs. DTC No. Detection Item DTC Detection Condition Trouble Area U0123 Lost Communication with Yaw Rate Sensor Module 3 seconds after the ignition switch is turned to ON, the vehicle is being driven at ...

Toyota Tundra Owners Manual