Pinpoint Test D: The Power Liftgate Does Not Operate Correctly - Reverses During the Power Close Operation
Power Liftgate
Pinpoint Test D: The Power Liftgate Does Not Operate Correctly - Reverses During the Power Close Operation
Normal Operation
When the power liftgate moves in the close direction, the Liftgate/Trunk Module (LTM) monitors the pinch strips and position sensor for obstacle detection. The LTM (Liftgate/Trunk Module) uses a 5-volt reference signal on circuit CPR52 (YE/VT) and a return signal on circuit RPR52 (VT/GY) for the left pinch strip. The LTM (Liftgate/Trunk Module) uses a 5-volt reference signal on circuit CPR51 (YE/OG) and a return signal on circuit RPR52 (VT/GY) for the right pinch strip. The right and left pinch strip return signal circuits are spliced together.
The position sensor receives 5 volts from the LTM (Liftgate/Trunk Module) through circuit CPR55 (GN/BU) and ground from the LTM (Liftgate/Trunk Module) through circuit RPR55 (WH/BU). The position sensor output signal is supplied to the LTM (Liftgate/Trunk Module) through circuits VPR53 (BU/WH) and VPR54 (BU/BN).
- DTC B107D (Obstacle Detected While Closing)- The LTM (Liftgate/Trunk Module) will set this DTC if an obstacle is detected during powered open/close during self-test only.
- DTC B2419 (Sensor 1 Invalid)- This DTC sets when the LTM (Liftgate/Trunk Module) detects the position sensor feedback signals are not correct.
- DTC B2420 (Sensor 2 Invalid)- This DTC sets when the LTM (Liftgate/Trunk Module) detects the position sensor feedback signals are not correct.
This pinpoint test is intended to diagnose the following:
- Mechanical binding
- Power liftgate latch striker alignment
- Power liftgate latch
- Power liftgate motor
- LTM (Liftgate/Trunk Module)
- Wedges
- Wiring, terminals or connectors
PINPOINT TEST D : THE POWER LIFTGATE DOES NOT OPERATE CORRECTLY - REVERSES DURING THE POWER CLOSE OPERATION
NOTICE: 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.
D1 CHECK THE MANUAL OPERATION OF THE LIFTGATE
- Turn the power liftgate OFF (disable) from the message center.
- While manually opening and closing the liftgate, check the liftgate for:
- liftgate/wedge alignment.
- strut operation (struts should push open liftgate when beyond half open).
- power liftgate rod (should move freely while manually opening and closing liftgate and should be securely mounted to the liftgate and bracket).
- power liftgate latch (should latch completely).
Does the liftgate open and close correctly?
Yes
If the liftgate reverses near the midpoint of travel, GO to D2.
If the liftgate reverses near or at the latch, GO to D11.
No
REPAIR as necessary. ALIGN as necessary. REFER to Liftgate . CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D2 CHECK THE POSITION SENSOR PID
- Ignition OFF.
- Connect: All LTM (Liftgate/Trunk Module) Connectors.
- Connect: Power Liftgate Motor C4332.
- Ignition ON.
- Open the liftgate to the full open position.
- Enter the following diagnostic mode on the scan tool: DataLogger- LTM (Liftgate/Trunk Module).
- Monitor the LTM (Liftgate/Trunk Module) PIDs OPT_SEN_1 and OPT_SEN_2 while slowly closing the liftgate.
Do both of the PID values alternate from ACTIVE to INACTIVE while the liftgate is moving?
Yes
GO to D11.
No
GO to D3.
D3 CHECK THE POSITION SENSOR POWER CIRCUIT
- Disconnect: Power Liftgate Motor C4332.
- Ignition ON.
- Measure the voltage between power liftgate motor C4332-4, circuit CPR55 (GN/BU), harness side and ground.
Is the voltage approximately 5 to 7 volts?
Yes
GO to D5.
No
GO to D4.
D4 CHECK THE POSITION SENSOR POWER CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174B-6, circuit CPR55 (GN/BU), harness side and power liftgate motor C4332-4, circuit CPR55 (GN/BU), harness side; and between LTM (Liftgate/Trunk Module) C4174B-6, circuit CPR55 (GN/BU), harness side and ground.
Is the resistance less than 5 ohms between LTM (Liftgate/Trunk Module) and power liftgate motor; and greater than 10,000 ohms between
LTM (Liftgate/Trunk Module) and ground?
Yes
GO to D16.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D5 CHECK THE POSITION SENSOR RETURN CIRCUIT
- Ignition OFF.
- Disconnect: Power Liftgate Motor C4332.
- Ignition ON.
- Measure the resistance between power liftgate motor C4332-9, circuit RPR55 (WH/BU), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to D7.
No
GO to D6.
D6 CHECK THE POSITION SENSOR RETURN CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174B-7, circuit RPR55 (WH/BU), harness side and power liftgate motor C4332-9, circuit RPR55 (WH/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to D16.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D7 CHECK THE POSITION SENSOR CIRCUITS FOR AN OPEN
- Ignition ON.
- Measure the voltage between power liftgate motor C4332-8, circuit VPR54 (BU/BN), harness side and ground; and between power liftgate motor C4332-3, circuit VPR53 (BU/WH), harness side and ground.
Is the voltage approximately 5 volts for both measurements?
Yes
INSTALL a new power liftgate motor. REFER to Power Liftgate Motor . CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
GO to D8.
D8 CHECK THE POSITION SENSOR CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between power liftgate motor C4332, harness side and LTM (Liftgate/Trunk Module) C4174B, harness side using the following chart:
Power Liftgate Motor Circuit LTM (Liftgate/Trunk Module) C4332-8 VPR54 (BU/BN) C4174B-21 C4332-3 VPR53 (BU/WH) C4174B-20
Are the resistances less than 5 ohms?
Yes
GO to D9.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D9 CHECK THE POSITION SENSOR CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between power liftgate motor C4332-3, circuit VPR53 (BU/WH), harness side and ground; and between power liftgate motor C4332-8, circuit VPR54 (BU/BN), harness side and ground.
Are the resistances greater than 10,000 ohms?
Yes
GO to D10.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D10 CHECK THE POSITION SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between power liftgate motor C4332-3, circuit VPR53 (BU/WH), harness side and ground; and between power liftgate motor C4332-8, circuit VPR54 (BU/BN), harness side and ground.
Is any voltage present?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
GO to D16.
D11 CHECK THE DETENT AND FORKBOLT SWITCH PID
- Enter the following diagnostic mode on the scan tool: DataLogger- LTM (Liftgate/Trunk Module).
- Operate the liftgate manually while monitoring the following LTM (Liftgate/Trunk Module) 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 unlatch position when the liftgate is open and completely out of the striker.
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 aActive Active In primary Active Inactive Inactive
a If the DETENTSW PID does not change state, attempt to manually rotate the forkbolt toward the latched position to change the current state.
Do the switch states agree with the table?
Yes
GO to D16.
No
GO to D12.
D12 CHECK THE OPERATION OF THE DETENT AND FORKBOLT SWITCHES
- Ignition OFF.
- Disconnect: LTM (Liftgate/Trunk Module) C4174B.
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174B, harness side and ground at each of the connector pins and each latch position specified by the chart below.
Liftgate Latch Position C4174B Circuit Resistance Fully Unlatched Pin 3, circuit CPR66 (GY/YE) Greater than 10,000 ohms aFully Unlatched Pin 5, circuit CPR64 (VT/OG) Less than 5 ohms Fully Unlatched Pin 4, circuit CPR65 (BU/GN) Less than 5 ohms Primary Pin 3, circuit CPR66 (GY/YE) Less than 5 ohms Primary Pin 5, circuit CPR64 (VT/OG) Greater than 10,000 ohms Primary Pin 4, circuit CPR65 (BU/GN) Greater than 10,000 ohms
a If resistance measured is less than 5 ohms, manually rotate the forkbolt to the latched position and retest.
Do the resistance values agree with the chart?
Yes
GO to D16.
No
GO to D13.
D13 CHECK THE DETENT AND FORKBOLT SWITCH GROUND CIRCUIT
- Disconnect: Liftgate Latch/Unlatch Assembly C4339.
- Measure the resistance between power liftgate latch/unlatch assembly C4339-8, circuit GD149 (BK/GY), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to D14.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D14 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR AN OPEN
- Measure the resistance between power liftgate latch/unlatch assembly C4339, harness side and LTM (Liftgate/Trunk Module) C4174B, harness side using the following chart:
Power Liftgate/Unlatch Assembly Circuit LTM (Liftgate/Trunk Module) C4339-2 CPR64 (VT/OG) C4174B-5 C4339-3 CPR65 (BU/GN) C4174B-4 C4339-5 CPR66 (GY/YE) C4174B-3
Is the resistance less than 5 ohms on all circuits?
Yes
GO to D15.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D15 CHECK THE DETENT AND FORKBOLT SWITCH CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between LTM (Liftgate/Trunk Module) C4174B-4, circuit CPR65 (BU/GN), harness side and ground; between LTM (Liftgate/Trunk Module) C4174B-5, circuit CPR64 (VT/OG), harness side and ground; then between LTM (Liftgate/Trunk Module) C4174B-3, circuit CPR66 (GY/YE), harness side and ground.
Are the resistances greater than 10,000 ohms on all circuits?
Yes
CHECK the power liftgate latch connector for bent or corroded connections on the component side and harness side. REPAIR as necessary.
INSTALL a new power liftgate latch. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.
D16 CHECK FOR CORRECT LTM (Liftgate/Trunk Module) OPERATION
- Disconnect all the LTM (Liftgate/Trunk Module) connectors.
- Check for:
- corrosion.
- pushed-out pins.
- Connect all the LTM (Liftgate/Trunk Module) connectors and make sure they are seated correctly.
- Make sure the liftgate is fully CLOSED.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new LTM (Liftgate/Trunk Module). REFER to Liftgate/Trunk Module (LTM) . REPEAT the LTM (Liftgate/Trunk Module) self-test.
No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the LTM (Liftgate/Trunk Module) self-test.