Whenever THE RAIN come, all signal lights simultaneously ON ?

On a dry day with everything working spray down different areas with a hose until you trip codes . That may pinpoint area to look at ..

 

WHAT YEAR, MODEL AND TYPE OF TRUCK??

 

We have had nothing but problems with that model and including the 2019-2023.

 

Our 2019 T680 will lose all dash lights and instruments occasionally when driving through heavy rain, has for 300K miles.

Impossible to replicate in the shop, just lived with it. Probably a rub at the spot coming through the firewall, but too cheap to yank the harness and replace it.

 

So T680 and ProStar/LT are the ones to avoid?

 

I don't know about the 680 or Prostar but I drove an LT for several years and had only one issue with it, the DEF sensor went out and derated the truck to 5mph. The cummins engine and electrical systems were flawless for me. I was taken out of the truck at 450000 miles and put in a new Cascadia for 8 days before I was shot.

 

LMFAO

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