Toyota Tundra Service Manual: Gain Rocker Switch (+) Circuit (C14A1,C14A2)

Toyota Tundra Service Manual / Brake / Brake Control / Dynamic Control Systems / Trailer Brake Control System / Gain Rocker Switch (+) Circuit (C14A1,C14A2)

DESCRIPTION

DTC No.

Detection Item

INF Code

DTC Detection Condition

Trouble Area

C14A1

Gain Rocker Switch (+) Circuit

21

With the ignition switch turned to ON and the IG terminal voltage from 11 to 14 V, an open circuit occurs continuously in the GAIN (+) selection button internal circuit or wire harness and connector stuck ON for 60 seconds or more
  • Trailer brake control switch
  • Trailer brake control ECU (Brake control with bracket relay)
  • Harness or connector

C14A2

Gain Rocker Switch (-) Circuit

31

With the ignition switch turned to ON and the IG terminal voltage from 11 to 14 V, an open circuit occurs continuously in the GAIN (-) selection button internal circuit or wire harness and connector stuck ON for 60 seconds or more
  • Trailer brake control switch
  • Trailer brake control ECU (Brake control with bracket relay)
  • Harness or connector

WIRING DIAGRAM

PROCEDURE

1.

INSPECT TRAILER BRAKE CONTROL SWITCH

(a) Turn the ignition switch off.

(b) Remove the trailer brake control switch.

Click here

(c) Inspect the trailer brake control switch.

Click here

OK:

The trailer brake control switch operates normally.

NG

REPLACE TRAILER BRAKE CONTROL SWITCH

OK

2.

CHECK HARNESS AND CONNECTOR (BRAKE CONTROL WITH BRACKET RELAY - TRAILER BRAKE CONTROL SWITCH)

(a) Disconnect the J172 trailer brake control ECU (brake control with bracket relay) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J172-6 (GA-) - J173-7 (GA-)

Always

Below 1 Ω

J172-6 (GA-) or J173-7 (GA-) - Body ground

Always

10 kΩ or higher

J172-15 (GA+) - J173-4 (GA+)

Always

Below 1 Ω

J172-15 (GA+) or J173-4 (GA+) - Body ground

Always

10 kΩ or higher

J173-6 (GND) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

TRAILER BRAKE PROBLEM CHECK

(a) Check the GAIN (+/-) selection button (trailer brake control switch) operation condition.

OK:

he GAIN (+/-) selection button (trailer brake control switch) has not been pushed and held for 1 minute or more.

OK

END
NG

REPLACE BRAKE CONTROL WITH BRACKET RELAY

    Slider Switch Circuit (C14A0)

    Output Circuit Temperature High / Over Current (C14A4,C14A6,C14AA)

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