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 > Occupant Classification System: Passenger Side Buckle Switch Circuit Malfunction (B1771)
DESCRIPTION The passenger side buckle switch circuit consists of the occupant classification ECU and the front seat inner belt RH. DTC B1771 is recorded when a malfunction is detected in the passenger side buckle switch circuit. Troubleshoot DTC B1771 first when DTCs B1771 and B1795 are output simul ...

Toyota Tundra Owners Manual