Toyota Tundra Service Manual: Hazard Warning Switch Circuit

DESCRIPTION

The combination meter assembly receives the air conditioning control assembly (hazard warning signal switch) ON signal and controls the operation of the hazard warning lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(a) Using the Techstream, read the Data List.

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Combination Meter

Tester Display

Measurement Item / Range

Normal Condition

Diagnostic Note

Hazard Flasher Switch

Hazard warning signal switch / OFF or ON

OFF: Hazard warning signal switch off

ON: Hazard warning signal switch on

-

OK:

Normal condition listed above are displayed.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

2.

INSPECT AIR CONDITIONING CONTROL ASSEMBLY (HAZARD WARNING SIGNAL SWITCH)

(a) Remove the air conditioning control assembly (hazard warning signal switch).

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(b) Inspect the air conditioning control assembly (hazard warning signal switch).

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NG

REPLACE AIR CONDITIONING CONTROL ASSEMBLY (HAZARD WARNING SIGNAL SWITCH)

OK

3.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY [HAZARD WARNING SIGNAL SWITCH] - COMBINATION METER ASSEMBLY AND BODY GROUND)

(a) Disconnect the J127 air conditioning control assembly (hazard warning signal switch) connector.

(b) Disconnect the J28 combination meter assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J127-1 (HAZ) - J28-20 (HAZ)

Always

Below 1 Ω

J127-5 (GND) - Body ground

Always

Below 1 Ω

J127-1 (HAZ) or J28-20 (HAZ) - Body ground

Always

10 kΩ or higher

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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    See More:

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