Toyota Tundra Service Manual: ECU Malfunction (C14A7)

Toyota Tundra Service Manual / Brake / Brake Control / Dynamic Control Systems / Trailer Brake Control System / ECU Malfunction (C14A7)

DESCRIPTION

DTC No.

Detection Item

INF Code

DTC Detection Condition

Trouble Area

C14A7

ECU Malfunction

71

72

73

74
  • INF Code: 71
    • ECU internal malfunction
  • INF Code: 72
    • Actuator operation driver IC malfunction in ECU
  • INF Code: 73
    • Actuator operation driver IC operates abnormally even though there is no valid brake request
  • INF Code: 74
    • When the trailer brake output is excessive while a brake request exists

Trailer brake control ECU (Brake control with bracket relay)

PROCEDURE

1.

CHECK DTC

(a) Clear the DTCs.

Click here

(b) Turn the ignition switch off.

(c) Turn the ignition switch to ON.

(d) Check if the same DTC is output.

Click here

Result

Proceed to

DTC is output.

A

DTCs are not output.

B
A

REPLACE BRAKE CONTROL WITH BRACKET RELAY

B

USE SIMULATION METHOD TO CHECK

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

    Power Supply Voltage Circuit (C1241)

    See More:

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    DESCRIPTION There may be a short circuit between the CAN main bus lines and/or CAN branch lines when the resistance between terminals 15 (CA5H) and 16 (CA5L) of the central gateway ECU (network gateway ECU) is below 54 Ω. Symptom Trouble Area Resistance between terminals 15 (CA5H) and 16 (CA5L) of ...

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