Diagnostic System Check: Notes
Diagnostic system check is an organized approach to identifying a problem created by an Anti-Lock Brake System (ABS) malfunction. This should be the starting point for any ABS diagnosis because it directs technician to next logical step in diagnosing a complaint.
NOTE:
Test numbers refer to numbers on diagnostic chart. Use only 10-megohm (minimum) DVOM for all voltage and resistance tests. For identification of circuits and terminals referenced in charts and text, see WIRING DIAGRAM
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- Indicates if EBCM is transmitting data.
- Checks for serial data line malfunction.
- Checks for proper connection of Tech 1 scan tool to DLC.
- Checks for open A/C-heater fuse.
- Checks for open fuse.
- Checks high resistance in EBCM battery feed circuit.
- Checks for current codes.
- Checks for proper ABS warning light operation.
- Checks for history codes.