• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Intake CMP Sensor 5V Reference | P0641 | P0340 | P0641 | P0341 |
Intake CMP Sensor Low Reference | -- | P0340 | -- | -- |
Intake CMP Sensor Signal | P0340 | P0340 | P0340 | -- |
Exhaust CMP Sensor 5V Reference | P0641 | P0365 | P0641 | P0366 |
Exhaust CMP Sensor Low Reference | -- | P0365 | -- | -- |
Exhaust CMP Sensor Signal | P0365 | P0365 | P0365 | -- |
The 4X camshaft position (CMP) sensor circuits consist of an engine control module (ECM) supplied 5V reference circuit, low reference circuit, and an output signal circuit. The CMP sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 4-tooth reluctor wheel attached to the camshaft. As each reluctor wheel tooth rotates past the CMP sensor, the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. The sensor returns a digital ON/OFF DC voltage pulse of varying frequency, with 4 varying width output pulses per camshaft revolution that represent an image of the camshaft reluctor wheel. The frequency of the CMP sensor output depends on the velocity of the camshaft. The ECM decodes the narrow and wide tooth pattern to identify camshaft position. This information is then used to determine the optimum ignition and injection points of the engine. The ECM also uses CMP sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, and for limp-home operation.
• | The engine is running. |
• | DTCs P0340 and P0365 run continuously when the above condition is met. |
The ECM does not receive 4 camshaft pulses within 3 seconds.
The ECM does not receive 4 camshaft pulses within 3 seconds
DTC P0340, and P0365 are Type B DTCs.
DTC P0340, and P0365 are Type B DTCs.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
• | Close routing of aftermarket electrical equipment |
• | Close to solenoids, motors, and relays |
Correct any wire harness routing or component placement conditions, if it is determined to be a possible source of electrical interference. |
⇒ | If greater than the specified value, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If less than the specified range, test the 5V reference circuit for an open/high resistance or short to ground. If the circuit tests normal, replace the K20 ECM. |
⇒ | If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
⇒ | 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 K20 ECM. |
⇒ | If greater than the specified range, test the affected signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM. |
⇒ | If the CMP active counter increments, replace the B23 CMP sensor. |
⇒ | If the CMP active counter does not increment, replace the K20 ECM. |
Note: You must perform the Circuit/System Testing before proceeding with Component Testing.
⇒ | If the sensor is loose, incorrectly installed, or damaged, repair or replace the CMP sensor. |
⇒ | If the parameter does not increment, replace the CMP sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |