ABS Warning Light Remains ON

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM: ABS Warning Light Remains ON

ABS Warning Light Remains ON

DESCRIPTION

- If any of the following is detected, the ABS warning light remains on:
1. The skid control ECU connectors are disconnected from the skid control ECU.
2. There is a malfunction in the skid control ECU internal circuit.
3. There is an open in the wire harness between the combination meter and skid control ECU.

HINT: Techstream may not be usable when there is a malfunction in the skid control ECU.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK DTC
(a) Is a DTC output for ABS?
Result:

B -- REPAIR CIRCUIT INDICATED BY OUTPUT DTC
A -- Continue to next step.
2. INSPECT SKID CONTROL ECU CONNECTOR SECURELY CONNECTED
(a) Check the ECU connector's connecting condition.
OK:
The connector should be securely connected.
NG -- CONNECT CONNECTOR TO ECU CORRECTLY
OK -- Continue to next step.
3. INSPECT BATTERY
(a) Check the battery voltage.
Standard voltage:
11 to 14 V
NG -- INSPECT CHARGING SYSTEM
OK -- Continue to next step.
4. INSPECT SKID CONTROL ECU (IG1 TERMINAL)
(a) WHEN USING TECHSTREAM
(1) Connect Techstream to the DLC3.
(2) Start the engine.
(3) Select Data List mode on Techstream.

ABS / VSC / TRAC:

(4) Read the voltage condition output from the ECU displayed on Techstream.
OK:
"Normal" is displayed.

(b) WHEN NOT USING TECHSTREAM
(1) Disconnect the skid control ECU connector.
(2) Turn the ignition switch to the ON position.
(3) Measure the voltage according to the value(s) in the table below.
Standard voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - COMBINATION METER)

(a) Disconnect the skid control ECU connector and combination meter connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. INSPECT SKID CONTROL ECU (GND TERMINAL)

(a) Disconnect the skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK -- Continue to next step.
7. INSPECT COMBINATION METER ASSEMBLY
(a) Check combination meter assembly (Initial Inspection and Diagnostic Overview).
NG -- REPLACE COMBINATION METER ASSEMBLY
OK -- REPLACE BRAKE ACTUATOR ASSEMBLY