2020 Silverado HD Seems to have forgotten it has a tailgate.

[Jwisco]

Have a 2020 Silverado 2500HD LTZ duramax with power up/down tailgate. None of the buttons work to open or close the tailgate, on tailgate, in cab, keyfob. No lights flash, no error message on screen, no actuator noise, nothing. Really annoying with toneau cover, but did manage to get that popped open.

 

I have pulled the plug on tailgate switch, continuity test it acts like it should. Held the button in for several seconds thinking maybe it was disabled like the multi pro gates can be, nothing.

 

F20 fuse in LH dash fuse box is good and has power to it. Pulled fuse for over 5 minutes and replaced, no change.

 

I have an appt with dealer's electronics guy in a couple weeks, after I get back from a vacation. Just wondering if I missed something thats easy to fix and can save the no doubt several hours they will have to dig into it. Why the F there is no manual backup option... I now have a very heavy 4 door sedan as its useless as a truck.

 

Edit to add: Camera and light on tailgate function normally.

Edited January 11, 2025 by Jwisco

[newdude]

12 minutes ago, Jwisco said:

Have a 2020 Silverado 2500HD LTZ duramax with power up/down tailgate. None of the buttons work to open or close the tailgate, on tailgate, in cab, keyfob. No lights flash, no error message on screen, no actuator noise, nothing. Really annoying with toneau cover, but did manage to get that popped open.

 

I have pulled the plug on tailgate switch, continuity test it acts like it should. Held the button in for several seconds thinking maybe it was disabled like the multi pro gates can be, nothing.

 

F20 fuse in LH dash fuse box is good and has power to it. Pulled fuse for over 5 minutes and replaced, no change.

 

I have an appt with dealer's electronics guy in a couple weeks, after I get back from a vacation. Just wondering if I missed something thats easy to fix and can save the no doubt several hours they will have to dig into it. Why the F there is no manual backup option... I now have a very heavy 4 door sedan as its useless as a truck.

 

Edit to add: Camera and light on tailgate function normally.

 

 

The tailgate system can set codes.  If you have a code reader good enough to read all vehicle modules, you'd be able to pull them and see what's there to pinpoint what to test or what could be bad.  

 

Here's a couple cheap options if you wanted to invest in some good ones:

 

OBDLinkMX - OBDLink® MX+ - Outstanding Bluetooth-Compatible OBD II Scan Tool

 

BlueDriver - https://us.bluedriver.com/

 

Topdon.  This one is rather advanced and has bi-directional control - TopScan – TOPDON USA

 

Or Topdon has the Carpal - CarPal – TOPDON USA

 

 

[Jwisco]

Dealer plugged their scan tool in and found no codes. After telling them what all I had done is when we set appt with their electronics guru up.

[Another JR]

Did you try unplugging and reconnecting the large tailgate connector near the spare tire?  

[Brad Feltham]

Any followup on this,  my 2020 Highcountry 2500HD Desiel has the same issue,  just been hesitant to take in cause it will doubtless cost a small fortune with no guarantee of a fix.

[Jwisco]

Turned out to be a corroded power wire to the liftgate module causing an undervoltage at module. You'd think that would cause a code of some kind instead of just ignoring the whole module.