Pinpoint Test Al : The Rear Gate Trunk Module (RGTM) Does Not Respond To The Diagnostic Scan Tool

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

AL1 CHECK THE RGTM (REAR GATE TRUNK MODULE) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: RGTM C4174A .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174A-4	Courtesy of FORD MOTOR COMPANY	Ground
C4174A-9	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes

GO to AL2

No	VERIFY BJB fuse 91 (30A) or BCM fuse 10 (5A) is OK. If OK, REPAIR the circuit. If not OK, Refer to the Wiring Diagram Information to identify the possible causes of the circuit short.

AL2 CHECK THE RGTM (REAR GATE TRUNK MODULE) GROUND CIRCUIT FOR AN OPEN

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174A-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes

GO to AL3

No	REPAIR the circuit.

AL3 CHECK THE MS-CAN (MEDIUM SPEED-CONTROLLER AREA NETWORK) CIRCUITS BETWEEN THE RGTM (REAR GATE TRUNK MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN

Disconnect: GWM C2431 .

Disconnect: RGTM C4174B .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-24	Courtesy of FORD MOTOR COMPANY	C2431-23
C4174B-23	Courtesy of FORD MOTOR COMPANY	C2431-22

Are the resistances less than 3 ohms?

Yes

GO to AL4

No	REPAIR the circuit in question.

AL4 CHECK FOR CORRECT RGTM (REAR GATE TRUNK MODULE) OPERATION

Ignition OFF.

Disconnect and inspect the RGTM 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 RGTM 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 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 RGTM. REFER to: Rear Gate Trunk Module (RGTM) .

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.