Toyota Tacoma manuals

Toyota Tacoma (2015-2018) Service Manual: Diagnosis System

DIAGNOSIS SYSTEM

1. DESCRIPTION

When troubleshooting a vehicle with the diagnosis system, the only difference from the usual troubleshooting procedure is connecting the Techstream to the vehicle and reading various data output from the vehicle's skid control ECU (brake actuator assembly).

The skid control ECU (brake actuator assembly) records DTCs when the ECU detects a malfunction in the ECU itself or in its circuits.

To check the DTCs, connect the Techstream to the DLC3 on the vehicle. The Techstream enables you to clear the DTCs, activate the various actuators, and check the Freeze Frame Data and Data List.

(a) Check the battery voltage.

Standard voltage:

11 to 14 V

If the voltage is below 11 V, recharge the battery before proceeding to the next step.

(b) Check the DLC3 (See page 2. DIAGNOSIS ).

2. DIAGNOSIS

(a) If the skid control ECU (brake actuator assembly) detects a malfunction, the ABS warning, brake warning and/or slip indicator lights will come on in order to warn the driver.

(b) The DTCs are simultaneously stored in memory. The DTCs can be read by connecting SST between terminals TC and CG of the DLC3 and observing the blinking pattern of the ABS warning and slip indicator lights, or by connecting the Techstream (See page (c) This system has a Test Mode (signal check) function (See page ).

(c) This system has a Test Mode (signal check) function (See page 3. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK ).

3. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK

(a) When the ignition switch is turned to ON, check that the ABS warning, brake warning, and slip indicator lights come on for approximately 3 seconds.

HINT:

  • When the brake fluid level is low, the brake warning light comes on.
  • If any of the indicators remains on or does not come on, proceed to troubleshooting for the light circuits listed below.

Trouble Area

See procedure

ABS warning light circuit (Remains on)

ABS warning light circuit (Does not come on)

Brake warning light circuit (Remains on)

Brake warning light circuit (Does not come on)

Slip indicator light circuit (Remains on)

Slip indicator light circuit (Does not come on)

Problem Symptoms Table
PROBLEM SYMPTOMS TABLE NOTICE: When replacing the skid control ECU (brake actuator assembly), sensor, etc., turn the ignition switch off. HINT: Use the table below to help determine the ...

Terminals Of Ecu
TERMINALS OF ECU Text in Illustration *a Component without harness connected (Skid Control ECU [Brake Actuator Assembly]) - - Ter ...

Other materials:

Open in Stop Light Switch Circuit (C1425)
DESCRIPTION The skid control ECU (brake actuator assembly) detects the brake operating conditions through a signal transmitted by the stop light switch. The skid control ECU incorporates a circuit to detect an open circuit. This DTC is output when an open circuit is detected in the stop light ...

Rear Occupant Classification Sensor LH Collision Detection (B1787)
DESCRIPTION DTC B1787 is set when the occupant detection ECU receives a collision detection signal, which is sent by the occupant classification sensor rear LH when an accident occurs. DTC B1787 is also set when the front seat with adjuster frame assembly RH is subjected to a strong impact, ...

Towing Tail Relay
Inspection INSPECTION PROCEDURE 1. INSPECT TOWING TAIL RELAY (a) Check the resistance. (1) Using an ohmmeter, measure the resistance between the terminals. Standard: Tester Connection Specified Condition 3-5 10 kΩ or higher ...

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