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Test Description

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

  1. 2:  Determines whether the DTC is current.
DTC C0121

Step Action Yes No
Schematic Reference: ABS Schematics 
1 Did you perform the Diagnostic System Check - Vehicle? Go to Step 2  Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
  1. Use the scan tool in order to clear the DTCs.
  2. Cycle the ignition to the OFF position.
  3. Start the engine.
  4. In park or neutral, release the brake.
  5. Turn OFF the engine.
Does the DTC reset?
Go to Step 3  Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3 Replace the electronic brake control module (EBCM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the repair?
Go to Step 4  -
4
  1. Use the scan tool in order to clear the DTCs.
  2. Cycle the ignition to OFF and then ON.
Does the DTC reset?
Go to Step 2  System OK