Griff1500

This thread came up while looking for my issue so maybe someone can answer my question before I take it to the dealership, I have the 4.3 v6 and my temp has always ran 160 or around that, recently I had the dealership replace a starter and did a leak test due to a evap leak code, well a day after getting it back I noticed my temp going up to 210 which it has never done, when I check if my fans are running I noticed only one is coming on, low speed with air off and turns up high when a/c is on but the other fan never turns on so I'm thinking that's why my temp is going up higher than normal, my question is should both fans be running especially when a/c is on, just want to know when I take it in so they don't try to b.s. me cause I have about a month left on the extended service contract and I'm sure they will try find any reason not to cover it.

Same issues here and did all the same fixes, cleaned the dash grounds, worked fine for a day, started looking for other grounds to check since for some the ground fixed it and others a different ground fixed it, so far I did the dash grounds, located as many of the frame grounds I could find and cleaned the battery terminals and even added some grounds but still no joy, next I'm going to tackle all the grounds I can find under the dash and behind the kick panels, I have gone through 4 batteries since I bought the truck new and currently have a new AGM battery in it so I want to fix this issue before it kills that one, I also noticed the issue comes on more often when the charging system is near 12v instead of 14v so I disconnected the sensor ring on the ground cable so it would stay at a higher charging voltage, if anyone has found a more definite solution to the problem please post.