Pinpoint Test U : The RTM (Radio Transceiver Module) Does Not Respond To The Diagnostic Scan Tool

WARNING: This page is about a different car, the 2020 Lincoln Corsair. However, it is still accessible from the selected car via links, so may be relevant.

Refer to MODULE COMMUNICATIONS NETWORK for schematic and connector information. Refer to PASSIVE ANTI-THEFT SYSTEM for schematic and connector information.
Normal Operation and Fault Conditions

The RTM communicates on the MS-CAN.

Possible Sources
- Fuse
- Wiring, terminals and connector
- RTM
Visual Inspection and Pre-checks
- Verify BCM fuse 17 (15A) is OK.

U1 CHECK THE RTM (RADIO TRANSCEIVER MODULE) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: RTM C9026.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C9026-6	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes

GO to U2

No	VERIFY BCM fuse 17 (15A) 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.

U2 CHECK THE RTM (RADIO TRANSCEIVER MODULE) GROUND CIRCUIT FOR AN OPEN

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C9026-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes

GO to U3

No	REPAIR the circuit.

U3 CHECK THE MS-CAN (MEDIUM SPEED-CONTROLLER AREA NETWORK) CIRCUITS BETWEEN THE RTM (RADIO TRANSCEIVER MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN

Disconnect: GWM C2431.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C9026-4	Courtesy of FORD MOTOR COMPANY	C2431-23
C9026-3	Courtesy of FORD MOTOR COMPANY	C2431-22

Are the resistances less than 3 ohms?

Yes

GO to U4

No	REPAIR the circuit in question.

U4 CHECK FOR CORRECT RTM (RADIO TRANSCEIVER MODULE) OPERATION

Ignition OFF.

Disconnect and inspect the RTM 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 RTM 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 RTM. REFER to: Radio Transceiver Module (RTM) .

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.