Test Procedure

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2005 Mercury Sable, 2005 Mercury Mountaineer, 2005 Mercury Monterey, 2005 Mercury Montego, and 2005 Mercury Mariner. However, it is still accessible from the selected car via links, so may be relevant.

JD1 CHECK THE CRANKSHAFT POSITION (CKP) SENSOR SIGNAL SENT TO THE PCM

NOTE: On certain applications with electronic throttle control (ETC), erroneous ignition and ETC-related DTCs may be set due to salt water intrusion into the crankshaft position (CKP) sensor harness connector. These DTCs are set in the following combinations:

P0320, P0351, and P2106
P0320, P0356, and P2106

Thoroughly clean the connector, pack with di-electric grease and retest. If the problem returns, continue the CKP sensor diagnosis.

Battery fully charged and starting system functioning properly.
Diagnostic tool connector connected.
Disable the inertia switch.
Key ON, engine OFF.
Access the PCM and monitor the RPM PID.
Crank the engine.

Is the RPM greater than 150 RPM?

Yes	No
For DTC P1336, GO to PINPOINT TEST HD STEP 30 . For all others, CKP, PCM and harness working properly. The concern is elsewhere. RETURN to SYMPTOM CHARTS - GASOLINE MODELS for further direction.	GO to JD2.

JD2 CHECK THE TIMING COVER, CKP SENSOR AND EXTERNAL TRIGGER WHEEL (OUTSIDE THE TIMING COVER) FOR OBVIOUS PHYSICAL DAMAGE

Key in OFF position.
Visually CHECK the timing cover, CKP sensor and external trigger wheel (outside the timing cover) for obvious physical damage.

Do any parts appear physically damaged?

Yes	No
REPAIR as necessary.	GO to JD3.

JD3 CHECK FOR PROPER CKP BIAS VOLTAGES IN THE PCM

CKP Sensor connector disconnected.
Key ON, engine OFF.

Measure the voltage between:

(+) CKP Sensor Connector, Harness Side	(-) Vehicle Battery
CKP+	Negative terminal
CKP-	Negative terminal

Are the voltages between 1 - 3 V?

Yes	No
GO to JD4.	GO to JD6.

JD4 CHECK THE CKP SENSOR RESISTANCE

Key in OFF position.

Measure the resistance between:

(+) CKP Sensor Connector, Component Side	(-) CKP Sensor Connector, Component Side
CKP+	CKP-

NOTE: The CKP sensor resistance values change significantly with temperature rise.

Is the resistance between 250 - 1K ohms?

Yes	No
GO to JD5.	INSTALL a new CKP sensor.

JD5 CHECK THE CKP HARNESS SHIELD GROUND

NOTE: The harness shield protects the CKP signal from electrical noise and is grounded at one end, typically near the PCM.

NOTE: Carry out the following resistance measurement between the CKP shield and the chassis ground.

Measure the resistance between:

(+) CKP_SHLD Assembly Connector, Harness Side	(-)
CKP_SHLD	Ground

Is the resistance less than 5 ohms?

Yes	No
GO to JD6.	REPAIR the open circuit. CHECK for a poor ground connection.

JD6 CHECK FOR SHORT BETWEEN CKP(+) AND CKP(-) IN THE HARNESS

Key in OFF position.
PCM connector disconnected.

Measure the resistance between:

(+) CKP Sensor Connector, Harness Side	(-) CKP Sensor Connector, Harness Side
CKP+	CKP-

Is the resistance greater than 10K ohms?

Yes	No
GO to JD7.	REPAIR the short circuit.

JD7 CHECK THE CKP CIRCUIT(S) FOR AN OPEN IN THE HARNESS

Measure the resistance between:

(+) CKP Sensor Connector, Harness Side	(-) PCM Connector, Harness Side
CKP-	CKP-
CKP+	CKP+

Are the resistances less than 5 ohms?

Yes	No
GO to JD8.	REPAIR the open circuit.

JD8 CHECK THE CKP CIRCUIT(S) FOR A SHORT TO GROUND IN THE HARNESS

Measure the resistance between:

(+) CKP Sensor Connector, Harness Side	(-) Vehicle Battery
CKP+	Negative terminal
CKP-	Negative terminal

Are the resistances greater than 10K ohms?

Yes	No
GO to JD9.	REPAIR the short circuit to GND.

JD9 CHECK THE CKP CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS

Key ON, engine OFF.

Measure the voltage between:

(+) PCM Connector, Harness Side	(-) Vehicle Battery
CKP+	Negative terminal
CKP-	Negative terminal

Is any voltage present?

Yes	No
REPAIR the short circuit to PWR.	INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .