Captiva

DTC P0341, P0346, P0366, or P0391 - LF1, LFW or LFX

The 4X camshaft position sensor circuits consist of an engine control module (ECM) supplied 5 V reference circuit, low reference circuit, and an output signal circuit. The camshaft position 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 camshaft position 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 camshaft position 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 uses the cylinder 1 intake camshaft position sensor to determine injector and ignition system synchronization. Also, the cylinder 1 intake camshaft position sensor is used to determine camshaft to crankshaft relationship, to control camshaft phasing, and for limp-home operation.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Ignition System Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Engine Control Module Scan Tool Information : LNQ  → LE5 w/GDS  → LF1 w/GDS for scan tool information

1. If DTC P0340, P0345, P0365, or P0390 are also set, diagnose those DTCs first
2. With the ignition OFF, inspect the engine wiring harnesses carrying the B23 camshaft position sensor circuits for the following conditions:

•	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.

3. Observe the following scan tool parameters are all incrementing:

•	Exhaust Camshaft Position Active Counter Bank 1

•	Intake Camshaft Position Active Counter Bank 1

•	Exhaust Camshaft Position Active Counter Bank 2

•	Intake Camshaft Position Active Counter Bank 2

4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Engine idling, move the related harnesses/connectors of the B23 camshaft position sensor while monitoring the scan tool Camshaft Position Variance parameter. The Camshaft Position Variance parameter should not change when moving the harness/connectors.

⇒	If the above condition exists, repair the harness/connectors as necessary.

2. Ignition OFF, inspect the B23 camshaft position sensor for correct installation.

⇒	If the B23 camshaft position sensor is loose, inspect the sensor and the O-ring for damage and replace as necessary.

3. Disconnect the harness connector at the B23 camshaft position sensor.
4. Ignition OFF, all vehicle systems OFF, this may take 2 minutes, test for less than 5 Ω between the low reference circuit terminal B and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.

5. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal A and ground.

⇒	If less than the specified range, test the 5 V reference circuit for a short to ground, or an open/high resistance. If the circuit tests normal, replace the K20 ECM.

⇒	If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.

6. Test for 4.8-5.2 V between the signal circuit terminal C and ground.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.

7. Ignition OFF, connect a 3 A fused jumper wire to the camshaft position signal circuit terminal C.
8. Ignition ON, momentarily touch the end of the fused jumper wire to ground while monitoring the scan tool camshaft position active counter. The camshaft position active counter should increment.

⇒	If the camshaft position active counter does not increment, replace the K20 ECM.

9. If all circuits test normal, replace the B23 camshaft position sensor.

Note: You must perform the Circuit/System Testing before proceeding with Component Testing.

1. Inspect the B23 camshaft position sensor for looseness and correct installation. Remove the camshaft position sensor from the engine and inspect the sensor and the O-ring for damage.

⇒	If the sensor is loose, incorrectly installed, or damaged, repair or replace the B23 crankshaft position sensor.

2. Connect the camshaft position sensor connector to the camshaft position sensor. Turn ON the ignition, with the engine OFF.
3. Ignition ON, observe the applicable camshaft position active counter parameter with a scan tool. Pass a steel object by the tip of the sensor repeatedly. The camshaft position active counter parameter should increment.

⇒	If the function does not perform as specified, replace the B23 camshaft position sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.