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DTC P0622: Generator Field Control Circuit: Testing

WARNING: This page is about a different car, the 2004 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition on, engine not running. With the DRBIII(R), read DTCs and record the related Freeze Frame data. If the Good Trip Counter is displayed and equal to zero, refer to the INTERMITTENT CONDITIONS  . Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  . If the Good Trip Counter is not displayed or equal to zero, go to next step.
  2. Turn the ignition off. Disconnect the Generator Field harness connector. Using a 12-volt test light, jumper it across the Generator Field harness connector. Turn ignition on, engine not running. With the DRBIII(R), actuate the Generator Field Driver circuit. If the test light illuminates brightly and flashes on and off, replace the Generator. Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  . If the test light does not illuminate or flash on and off, go to next step.
  3. Turn the ignition off. Disconnect the Generator Field harness connector. Using a 12-volt test connected to battery voltage, probe the (Z1) Gen Ground circuit in the Generator Field harness connector. If the test light illuminates brightly, go to next step. If the test light does not illuminate, repair the open in the (Z1) Gen Field Ground circuit. Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  .
  4. Turn the ignition off. Disconnect the Generator Field harness connector. Disconnect the PCM harness connector. Measure the voltage on the (K20) Gen Field Control circuit in the Generator Field harness connector. If the voltage is above 1.0 volt, repair the short to voltage in the (K20) Gen Field Control circuit. Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  . If the voltage is not above 1.0 volt, go to next step.
  5. Turn the ignition on. Disconnect the Generator Field harness connector. Disconnect the PCM harness connector. Measure the resistance between ground and the (K20) Gen Field Control circuit in the Generator Field harness connector. If the resistance is below 100 ohms, repair the (K20) Gen Field Control circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  . If the resistance is not below 100 ohms, go to next step.
    6. CAUTION: DO NOT probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool (8815) to perform diagnosis.
  6. Turn the ignition off. Disconnect the Generator Field harness connector. Disconnect the PCM harness connector. Measure the resistance of the (K20) Gen Field Control circuit from the Generator Field harness connector to the appropriate terminal of the Miller Special Tool (8815). If the resistance is below 5.0 ohms, go to next step. If the resistance is not below 5.0 ohms, repair the open in the (K20) Gen Field Control circuit. Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  .
    7. NOTE: Before continuing, check the PCM connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
  7. If there are no possible causes remaining, replace and program the Powertrain Control Module. See PROGRAMMING  . Perform POWERTRAIN VERIFICATION TEST VER-3 (NGC)  .
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