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Home >> Pontiac >> 2007 >> Grand Prix Base >> Repair and Diagnosis >> Brakes >> Anti-Lock Brake System, Traction Control System & Stability Control System >> Diagnostic Information and Procedures >> DTC C0121 >> Test Description
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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 Value(s) Yes No
Schematic Reference: Antilock Brake System Schematics 
Connector End View Reference: Antilock Brake System Connector End Views 
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
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 J 39700-530  Cable Adapter to the electronic brake control module (EBCM) harness connector only. See Special Tools .
  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 EBCM. Refer to Control Module References for replacement, setup, and programming.
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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