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Test Description

The number below refers to step number on the diagnostic table.

  1. 2:  This step determines if the DTC is current.
DTC C0121

Step Action Yes No
Schematic Reference:  ABS Schematics  
Connector End View Reference: ABS Connector End Views 
1 Did you perform the Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - ABS 
2 
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Use the scan tool in order to clear the DTCs.
Does the DTC reset?		 Go to Step 3  Go to Diagnostic Aids
3
  1. Connect the J 39700  universal pinout box using the. See Special Tools . J 39700-530 cable adapter to the EBCM harness connector only.
  2. Test the battery positive voltage circuit for an open, high resistance, or a short to ground. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 Go to Step 5  Go to Step 4 
4 Replace the Electronic Brake Control Module (EBCM). Refer to Electronic Brake Control Module Replacement .
Did you complete the replacement?		 Go to Step 5  -
5
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 Go to Step 2  System OK
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