Toyota Tundra Service Manual: Inspection

INSPECTION

PROCEDURE

1. INSPECT TRAILER BRAKE CONTROL SWITCH

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

8 (SRF) -5 (SRRT)

-

2 kΩ to 3.09 kΩ

8 (SRF) -16 (SRW1)

Manual trailer brake output slider operated to maximum position (100%)

Below 1 kΩ

Manual trailer brake output slider not operated (0%)

2 kΩ to 3 kΩ

8 (SRF) -14 (SRW2)

Manual trailer brake output slider operated to maximum position (100%)

2 kΩ to 3 kΩ

Manual trailer brake output slider not operated (0%)

Below 1 kΩ

8 (SRF) -15 (SRR)

-

12 Ω to 14 Ω

4 (GA+) -6 (GND)

GAIN (+) selection button pressed

Below 20 Ω

GAIN (+) selection button not pressed

100 kΩ or higher

4 (GA-) -6 (GND)

GAIN (-) selection button pressed

Below 20 Ω

GAIN (-) selection button not pressed

100 kΩ or higher

If the result is not as specified, replace the trailer brake control switch.

*a

Component without harness connected

(Trailer brake control switch)

*b

GAIN (+) selection button

*c

GAIN (-) selection button

*d

Manual trailer brake output slider

(b) Check that the LED illuminates.

(1) Apply battery voltage between the terminals of the trailer brake control switch, and check the illumination condition.

OK:

Measurement Condition

Switch Condition

Battery positive (+) →3 (TAIL)

Battery negative (-) → 1 (ILL-)

Illuminates

If the result is not as specified, replace the trailer brake control switch.

*a

Component without harness connected

(Trailer brake control switch)

*b

Indicator

    Components

    Installation

    See More:

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