Pinpoint Test F : Four-Wheel Drive (4WD) Clutch Field Coil - Electrical

WARNING: This page is about a different car, the 2018 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.

F1 CHECK FOR TCCM DTC'S

Ignition ON.

Enter the following diagnostic mode on the scan tool: TCCM KOEO Self-Test.

Are any DTCs present?

Yes	For DTC P1825:00, GO to F3 For DTC P1826:00, GO to F4 For DTC P1827:00, GO to F2 For all other DTC's, the DTC chart: TCCM.

No	The 4WD clutch field coil is electrically sound at this time. PERFORM 4WD functional test to verify system operation.

F2 CHECK CLUTCH CONTROL CIRCUIT FOR A SHORT TO GROUND

Ignition OFF.

Disconnect Transfer Case C350 .

Disconnect TCCM C2371B .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C350-2	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes

GO to F3

No	REPAIR the circuit. CLEAR the DTCs.

F3 CHECK CLUTCH CONTROL CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect Transfer Case C350 .

Positive Lead	Measurement / Action	Negative Lead
C350-2	Courtesy of FORD MOTOR COMPANY	C2371B-10

Is the resistance less than 3 ohms?

Yes

GO to F4

No	REPAIR the circuit. CLEAR the DTC's.

F4 CHECK CLUTCH CONTROL CIRCUIT FOR A SHORT TO VOLTAGE

Ignition OFF.

Disconnect TCCM C350 .

Connect TCCM C2371B .

Ignition ON.

Measure the voltage by carefully backprobing transfer case connector:

Positive Lead	Measurement / Action	Negative Lead
C350-2	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit. CLEAR the DTC's.

No	Replace field coil. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case .