Captiva

DTC P0340, P0345, P0365, or P0390 - 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. 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. This information is then used to determine the optimum ignition and injection points of the engine. The ECM also uses camshaft position sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, and for limp-home operation.

Note: The ECM detects engine movement by sensing the airflow through the MAF sensor when airflow is greater than 3 g/s, or by sensing crankshaft position sensor pulses.

DTCs P0340, P0345, P0365, and P0390 are Type B DTCs.

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. 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.

2. 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

3. 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. Ignition OFF, all vehicle systems OFF, this may take 2 minutes, disconnect the affected B23 camshaft position sensor connector.
2. Test for less than 3 Ω between the low reference circuit terminal 1 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 K20 ECM.

Note: The control module or the sensor may be damaged if the circuit is shorted to B+ voltage.

3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 3 and ground.

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

4. Test for 4.8-5.2 V between the signal circuit terminal 2 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 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.

5. Ignition ON, using a 3 A fused jumper wire connected to ground; momentarily touch the camshaft position sensor signal circuit terminal 2 repeatedly. The appropriate camshaft position active counter parameter should increment.

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

⇒	If the 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 crankshaft position sensor for looseness and correct installation. Remove the crankshaft 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 crankshaft position sensor connector to the crankshaft position sensor.
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.