Pinpoint Test B : The TCM (Transmission 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.

B1 CHECK THE TCM (TRANSMISSION CONTROL MODULE) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

Ignition OFF.

Disconnect: TCM C1750

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1750-31	Courtesy of FORD MOTOR COMPANY	Ground
C1750-48	Courtesy of FORD MOTOR COMPANY	Ground

Are the voltages greater than 11 volts?

Yes

GO to B2

No	VERIFY the BJB fuse 33 (10A) or 94 (15A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the OEM Wiring Diagrams to identify the possible causes of the circuit short.

B2 CHECK THE TCM (TRANSMISSION CONTROL MODULE) GROUND CIRCUIT FOR AN OPEN

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1750-50	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes

GO to B3

No	REPAIR the circuit.

B3 CHECK THE HS-CAN1 (HIGH SPEED-CONTROLLER AREA NETWORK 1) CIRCUITS BETWEEN THE TCM (TRANSMISSION CONTROL MODULE) AND THE DLC (DATA LINK CONNECTOR) FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1750-44	Courtesy of FORD MOTOR COMPANY	C251-6
C1750-43	Courtesy of FORD MOTOR COMPANY	C251-14

Are the resistances less than 3 ohms?

Yes

GO to B4

No	REPAIR the circuit in question.

B4 CHECK FOR CORRECT TCM (TRANSMISSION CONTROL MODULE) OPERATION

Ignition OFF.

Disconnect and inspect the TCM connector 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 TCM connector 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 TCM. Refer to: Transmission Control Module (TCM) .

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.