Circuit Description
The Camshaft Position (CMP) sensor indicates the camshaft position so that the Vehicle Control Module (VCM) can determine which cylinder is misfiring when a misfire is present. It is also used to check for a properly installed High Voltage switch. This is a type B DTC.
Conditions For Setting The DTC
The DTC will set if the engine is running and the cam sensor reference pulse is not seen once every 6 cylinders.
Action Taken When The DTC Sets
The VCM turns on the Malfunction Indicator Lamp (MIL) after 2 consecutive driving cycles with the fault active.
Conditions For Clearing The MIL/DTC
The VCM turns the MIL off after 3 consecutive driving trips without a fault condition present. A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles (coolant temperature has risen 40°F from the start-up coolant temperature and the engine coolant temperature exceeds 16O°F during that same ignition cycle) or the scan tool clearing feature has been used.
Diagnostic Aids
A poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation may cause an intermittent.
Thoroughly check any circuitry, that is suspected as causing the intermittent complaint, for the following conditions:
* Backed out terminals.
* Improper mating.
* Broken locks.
* Improperly formed or damaged terminals.
* Poor terminal to wiring connections.
* Physical damage to the wiring harness. Refer to Intermittents. See: Symptom Related Diagnostic Procedures Intermittent Condition
Test Description
The numbers below refer to the step numbers in the diagnostic table.
2. This step determines if the DTC P0340 is the result of a hard failure or an intermittent condition.
3. Determines if the voltage is available to the CMP through the VCM.
4. If the feed circuit is shorted to ground, the test lamp will be ON. This step determines if the circuit is open or shorted to ground. If the circuit is OK, then the VCM connections or VCM is faulty.
Tuesday, June 21st, 2011 AT 11:21 PM
