LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2008 >> Allure CXL >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System & Fuel System - 3.8L - DTC P0385 To DTC P2108 >> DTC P0385 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

  1. Ignition OFF, disconnect the IC module connector. Test for less than 3 ohms between the IC module ground circuit IC module terminal K and battery ground
    • If greater than the specified value, test the ground circuit for an open/high resistance.
  2. Ignition ON, test for B+ between the IC module ignition voltage circuit IC module terminal P and ground.
    • If less than the specified range, test the IC module ignition voltage circuit for an open/high resistance or short to ground.
  3. Connect the IC module.
  4. Disconnect the CKP sensor connector.
  5. Test for less than 1 ohm on the low reference circuit CKP sensor terminal C.
    • If greater than the specified value, test the low reference circuit for an open/high resistance.
  6. Ignition ON, test for more than 10 volts between the 12-volt reference circuit CKP sensor terminal D and ground.
    • If less than the specified range, test the 12-volt reference circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the IC module.
  7. Ignition ON, test for 4-8 volts between the signal circuit CKP sensor terminal A and ground.
    • If less than the specified range, test the signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the IC Module.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the IC Module.
  8. Ignition ON, using a jumper wire connected to ground, momentarily touch the CKP sensor 2 signal circuit CKP sensor terminal A repeatedly. The CKP Sensor parameter should increment.
    • If the CKP Sensor B parameter increments, replace the CKP sensor.
  9. Ignition OFF, disconnect the IC module connector. Ignition ON, using a jumper wire connected to B+, momentarily touch the low resolution engine speed signal circuit IC module terminal D repeatedly. The CKP Sensor parameter should increment.
    • If the CKP Sensor B parameter increments, replace the IC module.
    • If the CKP Sensor B parameter does not increment, test the low resolution engine speed signal for an open/high resistance, short to ground, or a short to voltage. If all circuits test OK, replace the PCM.
scientia non olet · About LEMON Manuals