2007 Pacifica powerlift gate problems.
 

My wife and I just bought a 2007 Pacifica. The rear liftgate isn't working. I hit the button on the remote or the one inside of the vehicle it does the same thing. It opens about 6 inches then reverses and latches back. If I open it manually and hit the button, it closes a few inches and reverses back to full open. I've read that it could be the shocks worn out causing the safety sensor to activate but before I buy one I wanted to check with you guys. The reason I'm doubting it's the shocks is because I disconnected the little arm that goes from the motor to the back door and tested the motor again with no weight on it the arm still behaves the same way, so that leads me to believe it's the safety sensor. Anyone know of a diagram I could look at because I have the trim off right now and can see the motor but I can't see where the safety sensor is.

Vehicles equipped with a power liftgate system utilize two pinch sensors. One pinch sensor is located on each side of the liftgate. These sensors look like weather-strips, however they consist of pieces of electrically conductive rubber (tapeswitch), wires, resistor, double sided tape, and a plastic carrier. Pinch sensors are used to provide additional protection against vehicle damage or personal injury caused by an obstacle being “pinched” between the liftgate and the liftgate opening of the vehicle.

The pinch sensors are wired in series with the power liftgate control module. If one pinch sensor becomes defective the module will act as though both sensors are defective. The power liftgate latch “Cinching” operation will be disabled if a problem is detected by the control module.

During a power liftgate “close” cycle, if either of the two conductive rubber strips (tapeswitch) of the pinch sensor come in contact with an obstacle, the pinch sensor circuit is completed. This tells the power liftgate control module that an obstruction is felt. The control module will stop the liftgate immediately and return it to the full open position.

DIAGNOSIS AND TESTING - PINCH SENSOR
WARNING: Use extreme caution when testing pinch sensor operation.

To verify power liftgate system and pinch sensor operation.

1. Cycle the power liftgate through two complete open and close cycles, during each of the final close cycles, with the liftgate in mid-travel, depress each of the pinch sensors to verify the power liftgate control module detects an obstruction and returns to the open position. If OK, pinch sensors and module are OK at this time. If NOT OK, go to Step #2
2. Remove the liftgate trim panel to access the inoperable pinch sensor's electrical connector. Using an ohmmeter, check for continuity on the two wires leading from the pinch sensor. While depressing the pinch sensor, continuity should be 300 ohms max. While NOT depressing the pinch sensor, continuity should be 10,000 ohms min. If OK, pinch sensor is OK at this time. If NOT OK, replace the pinch sensor.

My local Chrysler service manager tells me it is necessary to reprogram the computer if the liftgate latch is replaced. Really?