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Home >> Saturn >> 2007 >> Relay 3.9 W >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - DTC P0010 To DTC P0420 >> DTC P0340 or P0341 >> Circuit/System Testing
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Circuit/System Testing

P0340

  1. Ignition OFF, disconnect the 16-way engine harness to fuel injector harness connector.
  2. Test for less than 1 ohm of resistance between ECM side of the low reference circuit and ground.
    • If greater than the specified value, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  3. Ignition ON, test for 4.8-5.2 volts between the ECM side of the 5-volt reference circuit and ground.
    • If less than the specified range, test the 5-volt reference circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.
    • If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Ignition ON, test for 4.8-5.2 volts between the ECM side of the signal circuit and ground.
    • If less than the specified range, test the affected signal circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the ECM.
    • If greater than the specified range, test the affected signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  5. Ignition ON, using a jumper wire connected to ground, momentarily touch the CMP sensor signal circuit repeatedly. The CMP active counter parameter should increment.
    • If the CMP active counter does not increment, replace the ECM.
  6. Ignition OFF, inspect the wiring harness, from the 16-way connector to the CMP sensor, for any damage, opens, or shorts.
    • If the circuits test normal replace the CMP sensor.

P0341

  1. Ignition OFF, inspect the CMP sensor for looseness and correct installation.
    • If the sensor is loose, inspect the sensor and the O-ring for damage, replace as necessary.
  2. Inspect the engine for the following conditions:
    • Engine oil for debris
    • Camshaft reluctor wheel for damage
    • The timing chain, tensioner, and sprockets for wear or damage