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C1243

C1218/C1243: Pump Motor Ground Circuit Open, High Resistance or Shorted to Battery/Pump Motor Stalled








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.

CONDITIONS FOR SETTING THE DTC
^ 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.
^ 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 C1242.
^ 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.

INSPECTION





NOTE: Diagnostic flow table must be performed first before using this table.
Type 1