It is not that simple. It can be either one or both.
DTC C1218: PUMP MOTOR SHORTED TO VOLTAGE
1. Perform diagnostic system check. After performing diagnostic system check, go to next step.
2. Using scan tool, clear DTCs. Command pump motor on using AUTOMATED BLEED function on scan tool. Recheck DTCs. If DTC resets, go to next step. If DTC does not reset, problem is intermittent.
3. Turn ignition off. Remove EBCM from BPMV assembly. Check EBCM to BPMV connector for conditions which could cause an intermittent, such as damage, corrosion, poor terminal contact, or presence of brake fluid. If connector is okay and cavity is free of brake fluid, go to step 5. If a problem is found, go to next step.
4. If connector corrosion or damage is evident, replace BPMV and/or EBCM as necessary. If brake fluid is present, replace both BPMV and EBCM. After repairs, go to step 10.
5. Connect EBCM harness to EBCM with BPMV still separated. Using Connector Test Adapter Kit (J 35616-A) connect a test light between the pump motor circuits, on EBCM side. Command pump motor on using the AUTOMATED BLEED function using scan tool. If test light illuminates, go to step 9. If test light does not illuminate, go to next step.
6. Turn ignition off. Disconnect EBCM harness connector. Connect Universal Pinout Box (J 39700) using the Cable Adapter (J 39700-99) to EBCM harness connector only. Check resistance between pump motor ground circuit of universal pinout box and a known-good ground. If resistance 0-2 ohms, go to step 8. If resistance is not 0-2 ohms, go to next step.
7. Repair open or high resistance in pump motor ground circuit. After repairs, go to step 10. 8. Replace EBCM. After replacing EBCM, g to step 10.
9. Replace BPMV. After replacing BPMV, go to next step.
10. Using scan tool, clear DTCs. Ensure system voltage is greater than 8 volts and pump motor is commanded on. Recheck for DTCs. If DTC resets, go to step 2. If DTC does not reset, system is okay.
Thursday, May 14th, 2009 AT 12:27 AM