Pinpoint Test Ah : The TCCM (Transfer Case Control Module) Does Not Respond To The Diagnostic Scan Tool

WARNING: This page is about a different car, the 2018 Ford F-550 Super Duty, 2018 Ford F-450 Super Duty, 2018 Ford F-350 Super Duty, and 2018 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

AH1 CHECK THE TCCM (TRANSFER CASE CONTROL MODULE) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

Ignition OFF.

Disconnect: TCCM C2371A and C2371B .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C2371A-7	Courtesy of FORD MOTOR COMPANY	Ground

Positive Lead	Measurement / Action	Negative Lead
C2371B-6	Courtesy of FORD MOTOR COMPANY	Ground
C2371B-7	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes

GO to AH2

No	VERIFY BJB fuses 30 (10A), 69 (25A) and 80 (25A) (Electronic Shift On Fly (ESOF) or ELD) are OK. If OK, REPAIR the circuit. If not OK, REFER to the OEM Wiring Diagrams to identify the possible causes of the circuit short.

AH2 CHECK THE TCCM (TRANSFER CASE CONTROL MODULE) GROUND CIRCUITS FOR AN OPEN

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C2371B-1	Courtesy of FORD MOTOR COMPANY	Ground
C2371B-3	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes

GO to AH3

No	REPAIR the circuit.

AH3 CHECK THE HS-CAN2 (HIGH SPEED-CONTROLLER AREA NETWORK 2) CIRCUITS BETWEEN THE TCCM (TRANSFER CASE CONTROL MODULE) AND THE DLC (DATA LINK CONNECTOR) FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C2371A-10	Courtesy of FORD MOTOR COMPANY	C251-3
C2371A-9	Courtesy of FORD MOTOR COMPANY	C251-11

Are the resistances less than 3 ohms?

Yes

GO to AH4

No	REPAIR the circuit in question.

AH4 CHECK FOR CORRECT TCCM (TRANSFER CASE CONTROL MODULE) OPERATION

Ignition OFF.

Disconnect and inspect the TCCM connectors and related in-line connectors.

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

Reconnect the TCCM connectors and related in-line connectors. Make sure they seat and latch correctly.

Operate the system and determine if the concern is still present.

Is the concern still present?

Yes	CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new TCCM. Refer to: Transfer Case Control Module (TCCM) .

No	The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.