Electronic Brake Control Module: Testing and Inspection

Terminal Voltage Check Chart:

TERMINAL VOLTAGE CHECK CHART

Measuring ABS-ECU Voltage With Voltmeter Probe:

1. Connect a needle-nosed wire probe (paper clip etc.) to a voltmeter probe.
2. Insert the needle-nosed wire probe into each of the Antilock Brake System (ABS) - Electronic Control Module (ECU) connector terminals from the wire side, and measure the voltage while referring to the check chart.

NOTE:
a. Measure voltage with the ABS-ECU connectors connected.
b. You may find it convenient to pull out the ABS-ECU to make it easier to reach the connector terminals.
c. Checks don't have to be carried out in the order given in the chart.

CAUTION: Do not connect the positive (+) probe between connector terminal and ground. Other wise a wiring, the sensor, or ABS-ECU will be damaged.

3. If voltmeter shows any division from standard value, check the corresponding sensor, actuator and related electrical wiring, then repair or replace.
4. After repair or replacement, recheck with the voltmeter to confirm that the repair has corrected the problem.

ABS-ECU Connector Terminal Arrangement

ABS-ECU Connector Terminal Arrangement:

CAUTION:
1. Use the special tool (MB991356) to check the ABS-ECU terminal voltage and resistance.
2. The ABS-ECU connector terminal arrangement for troubleshooting is different from that on the special tool connector. So take the readings from the terminal numbers of the special tool when checking.

Terminal Resistance And Continuity Check Chart:

TERMINAL RESISTANCE AND CONTINUITY CHECKS
1. Turn the ignition switch to OFF.
2. Disconnect the ABS-ECU connector.
3. Measure the resistance and check for continuity between the terminals of the ABS-ECU harness-side connector while referring to the check chart.

NOTE:
a. When measuring resistance and checking continuity, a harness for checking contact pin pressure should be used instead of inserting a test probe.
b. Checks do not have to be carried out in the order given in this chart.

CAUTION: If resistance or continuity checks are performed on the wrong terminals, damage to the vehicle wiring, sensors, ABS-ECU, and/or ohmmeter may occur. Use care to prevent this!

4. If the ohmmeter shows any deviation from the normal condition, check the corresponding sensor, actuator and related electrical wiring, and then repair or replace.
5. After repair or replacement, recheck with the ohmmeter to confirm that the repair or replacement has corrected the problem.