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

(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 ).

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.