Lift-gate will not open

GC9654

MEMBER
2012 DODGE CARAVAN
3.3L
6 CYL
2WD
AUTOMATIC
140,000 MILES

No response from key fob or from console buttons. Lock doesn't seem to actuate, press key fob from outside no taillight flash or chime. I have opened it manually through the access panel and I did replace the latch mechanism with another used latch after finding switch on latch with high resistance. Leaning now towards pinch sensors. Did check lift-gate module in fuse box looked okay. Any input helpful.

3 Replies

KASEKENNY

MECHANIC
18,907 POSTS

Hi,

When you press the key fob and the lights don't flash or there is no chime tells me the power lift-gate module is not getting that signal. This will also explain why the other options to open the lift-gate are not working.

I suspect the PLGM has failed or there is a wiring issue going to it where it cannot open the gate.

I attached the operation of how this works. You will see that the buttons are hard wired but the key fob is sent via the CAN network to the PLGM which opens and closes the door. The fact that none of them are working points to this being the issue.

If we have a scan tool we can confirm all of this, otherwise we will need to access the module and check power and ground. However, if you are not familiar with CAN bus diagnostics then we will need to walk through that separately.

Basically on the CAN + you need 2.7 volts and CAN - you need 2.3 volts at the module. If you don't have any of these then we have a wiring issue.

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