Toyota Tundra Service Manual: ECU Power Source Circuit

Toyota Tundra Service Manual / Vehicle Interior / Air Conditioning / Air Conditioning System(for Manual Air Conditioning System) / 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
NG

REPLACE FUSE
OK

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
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
    Dtc Check / Clear

    How To Proceed With Troubleshooting

    See More:

    Toyota Tundra Service Manual > Lin Communication System: Diagnostic Trouble Code Chart
    DIAGNOSTIC TROUBLE CODE CHART HINT: If a trouble code is displayed during the DTC check, inspect the trouble areas listed for that code. For details of the code, refer to the "See page" below. Inspect the fuses and relays related to this system before inspecting the suspected areas below. LIN Commun ...

    Toyota Tundra Owners Manual

    Toyota Tundra Service Manual

    © 2026 Copyright www.ttundra.com
    0.0096