C1218

DTC C1218: Pump Motor Ground Circuit Open, High Resistance or Shorted to Battery






Circuit Description
Pump motor is contained within Brake Pressure Modulator Valve (BPMV). Pump motor ground is supplied through terminal E136-3 of EBCM. Battery voltage is supplied to EBCM terminal E136-15 when ignition switch is turned on. EBCM terminals E136-1 and E136-2 are "hot at all times."

DTC Detecting Condition
- DTC C1218 can only be set when ignition key is in "ON" position, pump motor is commanded on, and EBCM detected a short to power or high resistance in pump ground circuit.
- DTC C1243 can only be set when ignition key is in "ON" position, pump motor is commanded off just after a run command, and EBCM detected a seized or slowly moving pump motor.

Action Taken When the DTC Sets
- ABS relay opens, removing power from pump motor and solenoids.
- DTC (C1218 or C1243) is stored.
- ABS disabled, ABS warning light turns on.

Diagnostic Aids
Typical causes of DTC C1218.
- Poor terminal contact at terminal E136-3.
- Terminal E136-3 ground circuit shorted to voltage.
- Terminal E136-3 ground circuit open.
- Terminal E136-3 ground circuit high resistance to ground.
- Faulty EBCM.
Typical causes of DTC C1243.
- Poor terminal contact at terminal E136-3.
- Terminal E136-3 ground circuit high resistance. Terminal E136-3 ground circuit open. BPVM pump motor malfunction.
- Faulty EBCM.

DTC Troubleshooting





NOTE: "ABS Check: Type 1" must be performed first before using this flow.