Pinpoint Test A : The Power Liftgate Is Inoperative

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

A1 CHECK FOR LTM DTC B201A.
- Ignition ON.
- Using a diagnostic scan tool, carry out the LTM self-test.
Is DTC B201A present?

Yes GO to Pinpoint Test I .

No GO to A2.

A2 CHECK FOR OTHER DTCs FROM THE LTM

View the recorded results from the LTM self-test.

Are any LTM DTCs present?

Yes	For DTC B2908, GO to A6.For DTC B2418, B2419 or B2420, GO to A22.For DTC B2935, GO to A12.For DTC B2552, GO to A15.For DTC B2936, B2819, B2937 or B2939, GO to A16.For DTC B106E, GO to A19.For DTC B1179, B117A or B117B, GO to A31.
No	GO to A3.

A3 CHECK THE OPERATION OF THE POWER LIFTGATE SWITCHES
- Select PARK.
- NOTE: Make sure the power liftgate feature is enabled (ON) in the message center.
  
  Close the liftgate to the full closed position (manually if necessary).
- Activate the power liftgate from the front power liftgate control switch (instrument panel).
- Activate the power liftgate from the rear power liftgate control switch (left rear quarter panel).
- Activate the power liftgate from the exterior liftgate release switch.
Does the power liftgate operate from any switch?

Yes GO to Pinpoint Test B .

No GO to A4.

A4 CHECK THE LTM VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: LTM C4174A .

Measure:

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

Is the voltage greater than 11 volts?

Yes	GO to A5.
No	VERIFY Body Control Module (BCM) fuse 8 (10A) (Expedition) or 9 (10A) (Navigator) 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.

A5 CHECK THE LTM GROUND CIRCUIT FOR AN OPEN

Measure the resistance between LTM, Harness side and ground.

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

Is the resistance less than 3 ohms?

Yes	RECONNECT the power liftgate system electrical connectors. GO to A6.
No	REPAIR the circuit.

A6 CHECK THE LTM DETENT AND FORKBOLT SWITCH PIDs

Ignition ON.

Using a diagnostic scan tool, view the LTM PIDs.

Operate the liftgate manually while monitoring the following LTM PIDs :
- Detent switch status (DETENTSW)
- Forkbolt switch status (FORKBLT_S)
- Forkbolt secondary switch (FKSWSEC)

NOTE: The liftgate is in the primary position when the liftgate is in the full closed position. The liftgate is in the unlatched position when the liftgate is open and completely out of the striker. Make the liftgate is fully latched (second click) when monitoring the PIDs. If necessary, manually latch the forkbolt to the primary position.

Begin with the liftgate in the open position, then slowly close the liftgate into each of the latch positions specified by the table below.

Liftgate Latch Position

DETENTSW

FORKBLT_S

FKSWSEC

Fully Unlatched

Inactive ⁽¹⁾

Active

Primary

Active

Inactive

⁽¹⁾	If detent switch is active in the fully unlatched position, manually attempt to rotate the forkbolt toward the latched position.

Do the switch states agree with the table?

Yes	GO to A12.
No	GO to A7.

A7 CHECK THE OPERATION OF THE DETENT AND FORKBOLT SWITCHES IN THEIR CLOSED STATE

Ignition OFF.

Disconnect: LTM C4174B .

Close the liftgate and make sure it is fully latched.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-3	Courtesy of FORD MOTOR COMPANY	Ground

Open the liftgate and make sure the latch is completely out of the striker.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-4	Courtesy of FORD MOTOR COMPANY	Ground
C4174B-5	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances less than 3 ohms?

Yes	GO to A10.
No	GO to A8.

A8 CHECK THE DETENT AND FORKBOLT SWITCH GROUND CIRCUIT

Disconnect: Power Liftgate Latch C4339 .

Measure the resistance between power liftgate latch, harness side and ground.

Positive Lead	Measurement / Action	Negative Lead
C4339-8	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes	GO to A9.
No	REPAIR the circuit.

A9 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-3	Courtesy of FORD MOTOR COMPANY	C4339-2
C4174B-4	Courtesy of FORD MOTOR COMPANY	C4339-3
C4174B-5	Courtesy of FORD MOTOR COMPANY	C4339-1

Are the resistances less than 3 ohms?

Yes	CHECK the power liftgate latch connectors for bent or corroded connections on the component side and harness side and REPAIR as necessary. If no concern is found, INSTALL a new power liftgate latch. REFER to Handles, Locks, Latches and Entry Systems .
No	REPAIR the circuit in question.

A10 CHECK THE OPERATION OF THE DETENT AND FORKBOLT SWITCHES IN THEIR OPEN STATE

Close the liftgate and make sure it is fully latched.

Measure::

Positive Lead	Measurement / Action	Negative Lead
C4174B-4	Courtesy of FORD MOTOR COMPANY	Ground
C4174B-5	Courtesy of FORD MOTOR COMPANY	Ground

Open the liftgate and make sure the latch is completely out of the striker.

NOTE: If resistance measured is less than 3 ohms, manually rotate the forkbolt toward the latched position and retest.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-3	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes	GO to A35.
No	GO to A11.

A11 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR A SHORT TO GROUND

Disconnect: Power Liftgate Latch C4339 .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-3	Courtesy of FORD MOTOR COMPANY	Ground
C4174B-4	Courtesy of FORD MOTOR COMPANY	Ground
C4174B-5	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000?

Yes	CHECK the power liftgate latch connectors for bent or corroded connections on the component side and harness side and REPAIR as necessary. If no concern is found, INSTALL a new power liftgate latch. REFER to Handles, Locks, Latches and Entry Systems .
No	REPAIR the circuit in question.

A12 CHECK POWER LIFTGATE ROD OPERATION

Check for correct function of power liftgate rod and cable. Make sure:
- it is correctly attached to motor and liftgate.
- the cable turns with actuator.

Is the power liftgate rod operating correctly?

Yes	GO to A13.
No	INSTALL a new power liftgate rod. REFER to Power Liftgate Rod .

A13 CHECK FOR VOLTAGE AT THE POWER LIFTGATE MOTOR AND CLUTCH

Ignition ON.

Make sure the liftgate is in the fully closed position.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-1, back probe	Courtesy of FORD MOTOR COMPANY	Ground
C4332-2, back probe	Courtesy of FORD MOTOR COMPANY	C4332-7, back probe

While measuring the voltage at the power liftgate motor, have an assistant activate the power liftgate.

Are the voltages greater than 11 volts when the power liftgate is activated?

Yes	If a DTC was present, INSTALL a new power liftgate motor. REFER to Power Liftgate Motor .If no DTC was present, GO to A21.
No	GO to A14.

A14 CHECK THE MOTOR AND CLUTCH VOLTAGE OUTPUTS AT THE LTM

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174A-6, back probe	Courtesy of FORD MOTOR COMPANY	Ground
C4174A-8, back probe	Courtesy of FORD MOTOR COMPANY	Ground

While measuring the voltage at the LTM, have an assistant activate the power liftgate.

Are the voltages greater than 11 volts when the power liftgate is activated?

Yes	GO to A16.
No	GO to A15.

A15 CHECK THE LTM HIGH CURRENT VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: LTM C4174A .

Measure:

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

Is the voltage greater than 11 volts?

Yes	If diagnosing DTC B2552, GO to A35.If not diagnosing DTC B2552,, GO to A21 .
No	VERIFY Battery Junction Box (BJB) fuse 36 (30A) 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.

A16 CHECK THE POWER LIFTGATE MOTOR CLUTCH GROUND CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: LTM C4174A .

Disconnect: Power Liftgate Motor C4332 .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-7	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes	GO to A17.
No	REPAIR the circuit.

A17 CHECK THE POWER LIFTGATE MOTOR AND CLUTCH CIRCUITS FOR A SHORT TO VOLTAGE

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174A-5	Courtesy of FORD MOTOR COMPANY	Ground
C4174A-6	Courtesy of FORD MOTOR COMPANY	Ground
C4174A-8	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit in question.
No	GO to A18.

A18 CHECK THE POWER LIFTGATE MOTOR AND CLUTCH CIRCUITS FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174A-5	Courtesy of FORD MOTOR COMPANY	C4332-1
C4174A-6	Courtesy of FORD MOTOR COMPANY	C4332-5
C4174A-8	Courtesy of FORD MOTOR COMPANY	C4332-2

Are the resistances less than 3 ohms?

Yes	GO to A19.
No	REPAIR the circuit in question.

A19 CHECK THE POWER LIFTGATE MOTOR AND CLUTCH CIRCUITS FOR A SHORT TO GROUND

Ignition OFF.

Disconnect: LTM C4174A .

Disconnect: Power Liftgate Motor C4332 .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174A-5	Courtesy of FORD MOTOR COMPANY	Ground
C4174A-6	Courtesy of FORD MOTOR COMPANY	Ground
C4174A-8	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes	GO to A20.
No	REPAIR the circuit in question. If DTC B106E was present, CLEAR the DTCs and REPEAT the LTM self-test.

A20 CHECK THE POWER LIFTGATE MOTOR OPERATION

Connect: Power Liftgate Motor C4332 .

Manually unlatch the liftgate.

Open the liftgate approximately midway.

Connect:

Ground Jumper

Lead 1	Measurement / Action	Lead 2
C4174A-6	Courtesy of FORD MOTOR COMPANY	C4174A-1

NOTE: Do not apply power to the motor actuator circuit for more than a couple seconds or damage to the motor may occur.

Momentarily connect:

Voltage Jumper

Lead 1	Measurement / Action	Lead 2
C4174A-4	Courtesy of FORD MOTOR COMPANY	C4174A-5

Remove the fused jumper wires.

Does the power liftgate motor operate when the fused jumper wires are connected?

Yes	GO to A35.
No	INSTALL a new power liftgate motor. REFER to Power Liftgate Motor .

A21 MONITOR THE LTM POWER LIFTGATE MOTOR POSITION SENSOR PIDs
- Ignition OFF.
- Connect: LTM C4174A and C4174B .
- Connect: Power Liftgate Motor C4332 .
- Ignition ON.
- Open the liftgate to the full open position.
- Using a diagnostic scan tool, view the LTM PIDs.
- While slowly closing the liftgate, monitor the following LTM PIDs :
  - Liftgate optical sensor 1 status (OPT_SEN_1)
  - Liftgate optical sensor 2 status (OPT_SEN_2)
Do both PID values alternate from ACTIVE to INACTIVE while the liftgate is moving?

Yes GO to A31.

No GO to A22.

A22 CHECK THE LIFTGATE MOTOR POSITION SENSOR VOLTAGE SUPPLY CIRCUIT FOR VOLTAGE

Disconnect: Power Liftgate Motor C4332 .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-4	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage approximately 5 to 7 volts?

Yes	GO to A25.
No	GO to A23.

A23 CHECK THE LIFTGATE MOTOR POSITION SENSOR VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO GROUND

Ignition OFF.

Disconnect: LTM C4174B .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-6	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes	GO to A24.
No	REPAIR the circuit.

A24 CHECK THE LIFTGATE MOTOR POSITION SENSOR VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Measure:

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-6	Courtesy of FORD MOTOR COMPANY	C4332-4

Is the resistance less than 3 ohms?

Yes	GO to A35.
No	REPAIR the circuit.

A25 CHECK THE LIFTGATE MOTOR POSITION SENSOR RETURN CIRCUIT

Ignition OFF.

Disconnect: Power Liftgate Motor C4332 .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-9	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 50 ohms?

Yes	GO to A27.
No	GO to A26.

A26 CHECK THE LIFTGATE MOTOR POSITION SENSOR RETURN CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: LTM C4174B .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4174B-7	Courtesy of FORD MOTOR COMPANY	C4332-9

Is the resistance less than 3 ohms?

Yes	GO to A35.
No	REPAIR the circuit.

A27 CHECK THE LIFTGATE MOTOR POSITION SENSOR CIRCUITS FOR VOLTAGE

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-3	Courtesy of FORD MOTOR COMPANY	Ground
C4332-8	Courtesy of FORD MOTOR COMPANY	Ground

Are the voltages approximately 5 volts?

Yes	INSTALL a new power liftgate motor. REFER to Power Liftgate Motor .
No	GO to A28.

A28 CHECK THE LIFTGATE MOTOR POSITION SENSOR CIRCUITS FOR AN OPEN

Ignition OFF.

Disconnect: LTM C4174B .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-8	Courtesy of FORD MOTOR COMPANY	C4174B-21
C4332-3	Courtesy of FORD MOTOR COMPANY	C4174B-20

Are the resistances less than 3 ohms?

Yes	GO to A29.
No	REPAIR the circuit in question.

A29 CHECK THE LIFTGATE MOTOR POSITION SENSOR CIRCUITS FOR A SHORT TO GROUND

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-3	Courtesy of FORD MOTOR COMPANY	Ground
C4332-8	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes	GO to A30.
No	REPAIR the circuit in question.

A30 CHECK THE LIFTGATE MOTOR POSITION SENSOR CIRCUITS FOR A SHORT TO VOLTAGE

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4332-3	Courtesy of FORD MOTOR COMPANY	Ground
C4332-8	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit in question.
No	GO to A35.

A31 CHECK THE UNLATCH/CINCHING MOTOR CIRCUITS

Ignition OFF.

Disconnect: LTM C4174A .

Disconnect: LTM C4174A .

Close the power liftgate.

Connect:

Ground Jumper

Lead 1	Measurement / Action	Lead 2
C4174A-2	Courtesy of FORD MOTOR COMPANY	C4174A-1

NOTE: Do not apply power to the unlatch actuator circuit for more than a few seconds or damage to the motor may occur.

Momentarily connect:

Voltage Jumper

Lead 1	Measurement / Action	Lead 2
C4174A-3	Courtesy of FORD MOTOR COMPANY	C4174A-9

Remove the fused jumper wires.

Does the unlatch/cinching motor activate when fused jumper wires are connected?

Yes	GO to A35.
No	GO to A32.

A32 CHECK THE UNLATCH/CINCHING MOTOR CIRCUITS FOR AN OPEN

Disconnect: Liftgate Latch/Unlatch Assembly C4339 .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4339-5	Courtesy of FORD MOTOR COMPANY	C4174A-2
C4339-7	Courtesy of FORD MOTOR COMPANY	C4174A-3

Are the resistances less than 3 ohms?

Yes	GO to A33.
No	REPAIR the circuit in question.

A33 CHECK THE UNLATCH/CINCHING MOTOR CIRCUITS FOR A SHORT TO GROUND

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4339-5	Courtesy of FORD MOTOR COMPANY	Ground
C4339-7	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes	GO to A34.
No	REPAIR the circuit in question.

A34 CHECK THE UNLATCH ACTUATOR CIRCUITS FOR A SHORT TO VOLTAGE

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C4339-5	Courtesy of FORD MOTOR COMPANY	Ground
C4339-7	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit in question.
No	CHECK the power liftgate latch connectors for bent or corroded connections on the component side and harness side. and REPAIR as necessary. If no concern is found, INSTALL a new power liftgate latch. REFER to Handles, Locks, Latches and Entry Systems .

A35 CHECK FOR CORRECT LTM OPERATION

Disconnect all the LTM connectors.

Check for:
- corrosion (install new connectors or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

Reconnect all the LTM connectors and make sure they seat and latch correctly.

Operate the system and verify the concern is still present.

Is the concern still present?

Yes	CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions. If no TSBs address this concern, INSTALL a new LTM. REFER to Liftgate/Trunk Module (LTM) .
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.