My 2008 MDX started having a problem of the tailgate not opening. At first I thought it was the actuator but when I had the car running I went to put something in the back and it opened. So know I can open the tailgate if the ignition is in tfhe On position or the MDX is running.

I'm just looking for some advise on what to check to fix it.

Thanks.

 

The tailgate and alarm have different FOB ranges, Are you sure the conditions were similar when you tested with the engine running and not?
In my experience you have to be closer to the X when opening the tailgate as opposed when just disabling the alarm.

I would check the FOB battery first if you dont recall when was the last time it was replaced.

 

I'll get a new battery tomorrow and try. Although the FOB does unlock the rest of the doors.

 

you have to hold the rear hatch button down until you hear a beep!

 

I have an MDX without the power tailgate, so I don't have that button. I'm thinking that it might be the driver's door wiring. I've been looking into it more and it seems that a broken door harness can affect a control module. For awhile the beep when its locked with the FOB has been sporadic, and the driver's door lock button stopped working. I just thought they were just all dying after 13 years and not connected at all. I'll have to check the door out when it gets a little warmer here.