Pinpoint Test S : The HCM Module Does Not Respond To The Scan Tool

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

NOTE: Failure to disconnect the battery when instructed results in false resistance readings. Refer to Battery, Mounting and Cables .

S1 CHECK THE HCM MODULE VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: HCM C1600 .

Ignition ON.

Measure the voltage between:

Positive Lead		Negative Lead
Pin	Circuit	Pin	Circuit
C1600-1	CBB89 (VT/GY)	-	Ground

Courtesy of FORD MOTOR COMPANY

Is the voltage greater than 11 volts?

Yes	GO to S2.
No	VERIFY the Battery Junction Box (BJB) fuse 89 (10A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short.

S2 CHECK THE HCM GROUND CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: Negative Battery Cable.

Measure the resistance between:

Positive Lead		Negative Lead
Pin	Circuit	Pin	Circuit
C1600-25	GD123 (BK/GY)	-	Ground

Courtesy of FORD MOTOR COMPANY

Is the resistance less than 3 ohms?

Yes	GO to S3.
No	REPAIR the circuit.

S3 CHECK THE HS-CAN CIRCUITS BETWEEN THE HCM AND THE DLC FOR AN OPEN

Measure the resistance between:

Positive Lead		Negative Lead
Pin	Circuit	Pin	Circuit
C1600-8	VDB04 (WH/BU)	C251-6	VDB04 (WH/BU)
C1600-7	VDB05 (WH)	C251-14	VDB05 (WH)

Courtesy of FORD MOTOR COMPANY

Are the resistances less than 3 ohms?

Yes	GO to S4.
No	REPAIR the circuit in question.

S4 CHECK FOR CORRECT HCM OPERATION

Disconnect the HCM connector.

Repair:
- corrosion (replace connector or terminals - clean module pins)
- damaged or bent pins - replace terminals/pins
- pushed-out pins - replace pins as necessary

Connect the HCM connector and make sure it seats correctly.

Operate the system and verify the concern is still present.

Is the concern still present?

Yes	CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, discontinue this test and follow TSB instructions. If no TSBs address this concern, INSTALL a new HCM. REFER to Exterior Lighting .
No	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.