2019 Sierra 1500 MultiPro Upper Gate Dead

BostonBaked · July 18, 2023

Hey guys. I have a 2019 Sierra 1500 SLT (47K mi). My upper endgate on the multipro tailgate is no longer functioning; no click, no flash of the tail lights, absolutely nothing happens, even when you hold down the button for several seconds, etc., So it's not the override function. The main tailgate latch and rear cameras are functioning just fine, just not the upper tailgate.

I was vacationing in VT last week and it was working normally during that trip. Came home and power washed the VT silt off the truck. Next day the upper portion of the multipro tailgate is just dead, as described above.

Popped the upper tailgate panel caps off to expose the buttons and connected the upper tailgate release button's wire harness to a multimeter and was getting a successful continuity test while pressing the button. I then popped off the large plastic full tailgate cover to expose the actuators and wire harness. No visible damage to anything (some dead stink bugs though). I was able to manually release the upper endgate by flicking the manual release tabs on the actuator itself, and tried the button again and still no action from the actuators. Again, the main tailgate actuators and button is fine, the upper tailgate actuators are just dead.

Question: could power washing have shorted out an actuator?? The tailgate was closed and the toneau cover was on, but I did flush out the gap between the upper and lower gates as there was silt in there.

Does anyone know how to test the actuator? It has four pins on the driver side actuator. Part# 23392726.

By the way, I am aware of the previously mentioned toneau cover issue, and have folded it back, but have never had a problem with it releasing while on for the past few years. Double pressing the tailgate button on the key fob only drops the main tailgate.

I appreciate any insight. I searched and searched for hours and couldn't find a similar post/experience.

Edit: the actuator part numbers I have for the upper endgate are:

Driver side: 23362726 (new part number is 85530794)

Passenger side: 23362727 (new part number is 84903235)

If anyone knows how to test these, I'd really appreciate it!

Edited July 18, 2023 by BostonBaked
Add detail

gemarsh · July 19, 2023

I've read that the midgate button will show continuity but was still the problem. Lots of bad switches on the HD's due to the two drain holes right above the switch, on top of the tailgate.

BostonBaked · July 19, 2023

10 hours ago, gemarsh said:

I've read that the midgate button will show continuity but was still the problem. Lots of bad switches on the HD's due to the two drain holes right above the switch, on top of the tailgate.

Thanks for the feedback! Guess it makes sense to start with the $20 part before two $100 replacement latches!

Edit: to rule out the button being the issue, would it be reasonable to expect that if I connect the two pins on the harness that leads to the actuators that they trigger? I used my multimeter to touch both tips of the pins and nothing happened. Yet I do get continuity on the button side itself.

Edited July 19, 2023 by BostonBaked