Circuit Description
The EBCM/EBTCM Diagnostic System Check is an organized approach to identify problems associated with the EBCM/EBTCM. This check must be the starting point for any EBCM/EBTCM complaint, and will direct you to the next logical step in diagnosing the complaint. The EBCM/EBTCM is a very reliable component and is not likely the cause of the malfunction. Most system complaints are linked to faulty wiring, connectors, and occasionally to components. Understanding the ABS system and using the tables correctly will reduce diagnostic time and prevent unnecessary parts replacement.
Diagnostic Aids
| • | An intermittent failure in the electronic system may be very difficult to detect and to accurately diagnose. The EBCM/EBTCM tests for different malfunctions under different vehicle conditions. For this reason, a thorough test drive is often needed in order to repeat a malfunction. If the system malfunction is not repeated during the test drive, a good description of the complaint may be very useful in locating an intermittent malfunction. Faulty electrical connections or wiring causes most intermittent problems. When an intermittent condition is suspected, check the suspected circuits for the following conditions: |
| - | Poor mating of connector halves or backed out terminals |
| - | Improperly formed or damaged terminals |
| - | Wire chafing |
| - | Poor wire to terminal connections |
| - | Dirty or corroded terminals |
| - | Damage to connector bodies |
| • | If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while moving related wiring and connectors. This can often cause the malfunction to occur. Perform a thorough inspection of all related wiring and connectors pertaining to the history DTC stored. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 |
Does the Scan Tool communicate with the EBCM/EBTCM? | -- | ||
2 | Check for stored DTCs using the scan tool. Are there any current Diagnostic Trouble Codes? | -- | Go to Diagnostic Trouble Code (DTC) List for the Applicable DTC | |
3 | Cycle the ignition switch from the OFF to ON position, engine off. Does the ANTILOCK Indicator come On then go Off after several seconds? | -- | ||
4 | Cycle the ignition switch from the OFF to ON position, engine off. Does the LOW TRAC Indicator come On then go Off after several seconds? | -- | ||
5 | Cycle the ignition switch from the OFF to ON position, engine off. Does the TRAC OFF (Traction Control) Indicator come On then go Off after several seconds? | -- | ||
6 | Cycle the ignition switch from the OFF to ON position, engine off. Does the LOW TIRE Indicator come On then go Off after several seconds? | -- | ||
7 | Does the ANTILOCK Indicator come On and stay On? | -- | Go to ABS Indicator Always On | |
8 | Does the LOW TRAC Indicator come On and stay On? | -- | ||
9 | Does the TRAC OFF (Traction Control) Indicator come ON and stay ON? | -- | ||
10 | Does the LOW TIRE Indicator come On and stay On? | -- | ||
11 | Are there any history DTCs? | -- | System OK | |
12 |
Did the history DTC set as a current DTC while the vehicle was being driven? | -- | Go to Diagnostic Trouble Code (DTC) List for the Applicable DTC | System OK |
