Pinpoint Test B : The TCM (Transmission Control Module) Does Not Respond To The Diagnostic Scan Tool

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

Ignition OFF.

Disconnect: TCM C1822

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1822-31	Courtesy of FORD MOTOR COMPANY	Ground
C1822-48	Courtesy of FORD MOTOR COMPANY	Ground

Are the voltages greater than 11 volts?

Yes

GO to B2

No	VERIFY the BJB fuses 14 (15A) and 83 (15A) are OK. If OK, REPAIR the circuit in question. If not OK, Refer to the Wiring Diagram Information 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
C1822-50	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
C1822-44	Courtesy of FORD MOTOR COMPANY	C251-6
C1822-43	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.

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. Make sure it seats and latches correctly.

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

Is the concern still present?

Yes

CHECK OASIS for any applicable service articles: TSB, General Service Bulletin (GSB), SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles 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.