Fuel System > Engine Control System > P0346 Camshaft Position Sensor A Circuit Range/Performance (Bank 2)

Component Location

General Description

The Camshaft Position Sensor (CMPS) is a sensor that detects the compression TDC of the NO. 1 cylinder. The CMPS consists of a hall type sensor and a target on the end of the intake camshaft. When the target triggers the sensor, the sensor voltage is 5V. If not, the sensor voltage is 0V. These CMPS signal is sent to the PCM and the PCM uses the CMPS signal for synchronizing the firing of sequential fuel injectors.

DTC Description

Checking oputput signals from CMP during engine running, if the expected number of cam tooth count is not observed, PCM sets P0346. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.

DTC Detecting Condition

Item

Detecting Condition

Possible cause

DTC Strategy

•	Check if CAM sensor is synchronized correctly

•	Poor connection

•	Open or short in harness

•	electrical noise

•	Target wheel

•

CMPS

•

PCM

Enable Conditions

•	Engine running

Threshold value

•	Cam tooth count ≠ 6

Diagnosis Time

•	Continuous

MIL On Condition

•	2 driving cycles

Schematic Diagram

Signal Wavefrom And Data

This example shows a typical Crankshaft Position Sensor(CKPS) and Camshaft Position Sensor(CMPS) waveform at idle. The PCM controls the injection and ignition timing by using these signals. Generally CKPS signal is used to detect the piston's position and CMPS signal is used to detect the Top Dead Center of each cylinder.

Monitor DTC Status

Check DTC Status

(1)	Connect scantool to Data Link Connector(DLC).

(2)

IG "ON".

(3)	Select "DTC" button, and then Press "DTC Status" to check DTC's information from the DTCs menu.

(4)	Read "DTC Status" parameter.

(5)

Is parameter displayed "Present fault"?

	▶ Go to "Terminal and connector inspection" procedure.
	▶ Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

Terminal And Connector Inspection

1.	Many malfunctions in the electrical system are caused by poor harness and terminal condition. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

2.	Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

	▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure
	▶ Go to "Power Circuit Inspection" procedure.

Power Circuit Inspection

■ Check voltage

1.	IG "OFF" and disconnect CMPS(B2) connector.

2.	IG "ON" and ENG "OFF"

Measure voltage between power terminal of CMPS(B2) harness connector and chassis ground.

Specification : Approx. 5V

Is the measured voltage within specification?

	▶ Go to "Signal Circuit Inspection" procedure.
	▶ Repair open or short to ground in harness, and go to "Verification of Vehicle Repair" procedure.

Signal Circuit Inspection

■ Check voltage

1.	IG "OFF" and disconnect CMPS(B2) connector.

2.	IG "ON" and ENG "OFF"

Measure voltage between signal terminal of CMPS(B2) harness connector and chassis ground.

Specification : Approx. 5V

Is the measured voltage within specification?

	▶ Go to "Check short in harness" as follows.
	▶ Go to "Check open in harness" as follows.

■ Check short in harness

1.	IG "OFF" and disconnect CMPS(B2) connector.

Measure resistance between signal and power terminals of CMPS(B2) harness connector.

Specification : Infinite

Is the measured resistance within specification?

	▶ Go to "Check short to ground in harness" as follows.
	▶ Repair short in harness, and go to "Verification of Vehicle Repair" procedure.

■ Check short to ground in harness

1.	IG "OFF" and disconnect CMPS(B2) connector and PCM connector.

Measure resistance between signal terminal of CMPS(B2) harness connector and chassis ground.

Specification : Infinite

Is the measured resistance within specification?

	▶ Go to "Ground Circuit Inspection" procedure.
	▶ Repair short to ground in harness, and go to "Verification of Vehicle Repair" procedure.

■ Check open in harness

1.	IG "OFF" and disconnect CMPS(B2) connector and PCM connector.

Measure resistance between signal terminal of CMPS(B2) harness connector and CMPS(B2) signal terminal of PCM harness connector.

Specification : Below 1Ω

Is the measured resistance within specification?

	▶ Go to "Ground Circuit Inspection" procedure.
	▶ Repair open in harness, and go to "Verification of Vehicle Repair" procedure.

Ground Circuit Inspection

■ Check open in harness

1.	IG "OFF" and disconnect CMPS(B2) connector and then IG "ON".

2.	Measure voltage between signal terminal of CMPS(B2) harness connector and chassis ground.(Measurement "A")

Measure voltage between signal and ground terminals of CMPS(B2) harness connector.(Measurement "B")

Specification : Measurement "A" - Measurement "B" = Approx. below 200mV

Is the measured voltage within specification?

	▶ Go to "Component Inspection" procedure.
	▶ Repair open or contact resistance in harness, and go to "Verification of Vehicle Repair" procedure.

Component Inspection

■ Check CMPS

1.	IG "OFF" and connect scantool.

2.	ENG "ON" and Measure signal waveform at signal terminal of CMPS. Reference signal waveform :

Is the measured signal waveform normal?

	▶ Substitute with a known - good PCM and check for proper operation. If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
	▶ Check the electrical noise of siganl waveform, and go to "Check target wheel of CAM shaft" as follows.

There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by PCM. After testing PCM on the vehicle, use this function to reuse the PCM on the others.

■ Check target wheel of CAM shaft

IG "OFF"

2.	Remove the cover of cylinder head and check target wheel state of bank 2.

Is the target wheel state normal?

	▶ Substitute with a known - good CMPS and check for proper operation. If the problem is corrected, replace CMPS and go to "Verification of Vehicle Repair" procedure.
	▶ Repair or replace it, and go to "Verification of Vehicle Repair" procedure.

Verification Of Vehicle Repair

After a repair, it is essential to verify that the fault has been corrected.

1.	Connect scantool and select "DTC" button.

2.	Press "DTC Status" button and confirm that "DTC Readiness Flag" indicates "Completed". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions

3.	Read "DTC Status" parameter

Is parameter displayed "History(Not Present) fault"?

	▶ System performing to specification at this time. Clear the DTC
	▶ Go to the applicable troubleshooting procedure.