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 .gif)
).
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.
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:
Parking Brake Switch Circuit
DESCRIPTION
This circuit is from the parking brake switch assembly to the radio and display
receiver assembly.
WIRING DIAGRAM
PROCEDURE
1.
CHECK VEHICLE SIGNAL
(a) Display the "Vehicle Signal Check Mode" screen (See page
).
...
Reassembly
REASSEMBLY
PROCEDURE
1. INSTALL REAR WHEEL CYLINDER CUP KIT
(a) Provisionally tighten the bleeder plug to the rear wheel brake cylinder,
and install the bleeder plug cap.
(b) Apply lithium soap base glycol grease to 2 new cylinder cups and the 2 pistons.
(c) Install the cylinder cup onto ea ...
Precaution
PRECAUTION
1. IGNITION SWITCH EXPRESSIONS
(a) The type of ignition switch used on this model differs according to the specifications
of the vehicle. The expressions listed in the table below are used in this section.
Expression
Ignition Switch (Position)
Engine ...
