Pinpoint Test D : The Message Center Does Not Agree With Actual Trailer Connection

WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

D1 CHECK TBM (TRAILER BRAKE CONTROL MODULE) DTC (DIAGNOSTIC TROUBLE CODE)
- Ignition ON.
- Using a diagnostic scan tool, carry out the TBM self-test.
Are any Diagnostic Trouble Codes (DTCs) present in the TBM?

Yes DIAGNOSE all TBM Diagnostic Trouble Codes (DTCs).

No GO to D2

D2 CHECK MESSAGE CENTER TOWING STATUS

NOTE: Before performing any testing check customers message center setting's in TOWING . Set TRAILER BRAKE TYPE to Electric or misdiagnosis could occur.

NOTE: Unless instructed otherwise, carry out all pinpoint tests without a trailer or emulator connected to the vehicle.
- Ignition ON.
  NOTE: Observe message center when turning ignition to ON, message only displayed for limited amount of time.
Does the vehicle indicate a trailer is connected in the message center?

Yes GO to D3

No GO to D4

D3 CHECK TBM (TRAILER BRAKE CONTROL MODULE) TRAILER CONSTANT PID STATUS

NOTE: Before performing any testing check customers message center setting's in TOWING . Set TRAILER BRAKE TYPE to Electric or misdiagnosis could occur.

NOTE: Unless instructed otherwise, carry out all pinpoint tests without a trailer or emulator connected to the vehicle.
- Ignition ON.
- Using a diagnostic scan tool, access the TBM PID's (parameter identifications).
- Apply the vehicle brakes for at least 2 seconds.
- Monitor the TBM PID:
  CONSTANT
Does the CONSTANT PID display ON?

Yes GO to D5

No GO to D4

D4 CHECK TRM (TRAILER MODULE) TRAILER ON PID STATUS

Using a diagnostic scan tool, access the TRM PID's (parameter identifications).

Apply the vehicle brakes for at least 2 seconds.

Monitor the TRM PID:
TRAILER ON

Does the TRAILER ON PID display ON?

Yes	REFER to: TRAILER LAMPS

No	The condition causing the concern is not present at this time. The concern is intermittent and may have been caused by improper wiring on the trailer, a loose or corroded 7-pin connector or improper messages on the HS-CAN2.

D5 CHECK THE 7 PIN TRAILER TOW CONNECTOR TRAILER BRAKES CIRCUIT FOR A SHORT TO GROUND

Measure:

5th Wheel Inside Truck Bed

Positive Lead	Measurement / Action	Negative Lead
Refer to C439-3	Courtesy of FORD MOTOR COMPANY	Ground

Rear Bumper

Positive Lead	Measurement / Action	Negative Lead
Refer to C4099-3	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes

GO to D6

No	REPAIR the circuit.

D6 CHECK THE 7 PIN TRAILER TOW CONNECTOR TRAILER BRAKES CIRCUIT FOR A SHORT TO VOLTAGE

Ignition ON.

Measure:

5th Wheel Inside Truck Bed

Positive Lead	Measurement / Action	Negative Lead
Refer to C439-3	Courtesy of FORD MOTOR COMPANY	Ground

Rear Bumper

Positive Lead	Measurement / Action	Negative Lead
Refer to C4099-3	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit.

GO to D7

D7 VERIFY ALL WIRING CONNECTIONS
- Disconnect TBM and related in-line connectors.
- Using a good light source, inspect all disconnected electrical connectors for the following:
  - corrosion - install new connector or terminal and clean the module pins
  - damaged or bent pins - install new terminals or pins
  - pushed-out pins - install new pins as necessary
  - spread terminals - install new terminals as necessary
Are the connectors free of corrosion, damaged pins, bent pins, pushed-out pins and spread terminals?

Yes GO to D8

No REPAIR the affected connectors or terminals. Refer to GROUNDS for schematic and connector information.

D8 CHECK FOR CORRECT TBM (TRAILER BRAKE CONTROL MODULE) OPERATION

Connect all in-line electrical connectors. Make sure they seat and latch correctly.

Connect TBM C2142. Make sure it seats and latches correctly.

Operate the system and verify 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 the TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new TBM. REFER to: Trailer Brake Control Module (TBM) .

No	The condition causing the concern is not present at this time. The concern is intermittent and may have been caused by a loose or corroded connector, low battery voltage or an excessive load on the HS-CAN1 or HS-CAN2.