The ratchet, pawl, and sector switches are part of the liftgate latch assembly and are used by the liftgate module (LGM) to determine the state of the latch during the process of latching or unlatching. The ratchet and pawl switches will be inactive when the primary and secondary latches are latched, and the sector switch will be active during the power cinch function. Each of the latch switch signal circuits are supplied battery voltage through a resistor and monitored within the LGM. The latch switches share a common low reference circuit from the LGM and when the switch contacts close the signal circuit goes low and the LGM determines the switch to be active. The full open switch is a limit switch mounted on the gear motor assembly alongside the swing arm gear. The full open switch signal circuit is supplied battery voltage through a resistor and monitored within the LGM. When the liftgate reaches the full open position, the switch signal circuit is closed to the low reference circuit and the signal circuit voltage goes low.

The system voltage is 9-16 volts.

B153A 00

The LGM detects a fault in any of the following switch signal circuits:

B153A 08

When the LGM detects a loss of B+ voltage, an open/high resistance in the sensor signal circuit, an open/high resistance in the liftgate latch low reference circuit, or any incorrect combination of signals from the following switch inputs:

DTC B153A may be set when the vehicle is driven while the liftgate is open, as when the owner transports a large package in the rear of the vehicle. The DTC will become history after the liftgate is closed and does not affect normal liftgate operation.

Note: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power for the appropriate procedure.

Whenever the LGM loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the LGM.

Schematic Reference

Liftgate Schematics

Connector End View Reference

Vehicle Access Connector End Views

Description and Operation

Rear Hatch/Gate Description and Operation

Electrical Information Reference

Scan Tool Reference

1. Ignition ON, doors unlocked, transaxle in Park, liftgate closed, disable the power liftgate by pressing the liftgate enable/disable button on the I/P switch assembly.
2. Observe the scan tool LGM Latch Sector Sw parameter while manually opening the liftgate, the parameter should change from Inactive to Active to Inactive when opening the liftgate.
3. Observe the scan tool LGM Latch Pawl Sw. and LGM Latch Ratchet Sw. parameters while manually opening the liftgate, the parameters should change from Inactive to Active.

1. Ignition OFF, disconnect the X2 harness connector at the LGM
2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 3 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, replace the LGM.

3. Ignition OFF, connect the X2 harness connector at the LGM and disconnect the harness connector at the liftgate latch assembly.
4. Test for less than 10 ohms between the low reference circuit terminal 2 and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the LGM.

5. Ignition ON, verify the scan tool LGM Latch Pawl Sw. parameter is Inactive.

⇒	If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the LGM.

6. Verify the scan tool LGM Latch Ratchet Sw. parameter is Inactive.

⇒	If not the specified value, test the signal circuit terminal 6 for a short to ground. If the circuit tests normal, replace the LGM.

7. Verify the scan tool LGM Latch Sector Sw. parameter is Inactive.

⇒	If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the LGM.

8. Install a 3A fused jumper wire between the signal circuit terminal 5 and low reference circuit terminal 2. Verify the scan tool LGM Latch Pawl Sw. parameter is Active.

⇒	If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.

9. Install a 3A fused jumper wire between the signal circuit terminal 6 and low reference circuit terminal 2. Verify the scan tool LGM Latch Ratchet Sw. parameter is Active.

⇒	If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.

10. Install a 3A fused jumper wire between the signal circuit terminal 4 and low reference circuit terminal 2. Verify the scan tool LGM Latch Sector Sw. parameter is Active.

⇒	If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the LGM.

11. If all circuits test normal, test or replace the liftgate latch assembly.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.