By - 2006Silver
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There should be 2 fans. One is a cooling fan that should kick on at a set temp. The other is the AC fan that should come on as soon as the AC is on. If the main cooling fan is not coming on then when you turn the AC on that fan is doing an adequate enough job of cooling the truck. It most likely will not as the outside temp rises. Check your fuses and relay to the cooling fan. If they are good get the truck up to temp and test the hot wire to the cooling fan with a test light. If you have power your fan is toast.
In addition to this, some older vehicles with electric fans used a different temp sensors for the dash and the computer. If have access to an OBDII scanner that reads data it might be worth A look to see if the computer is getting an accurate temp to turn the fans on. Compare it to the dash gauge for quick reference. They default to -40 if the sensor does not read
True. Didn’t think about that. Had that same issue recently with a Ford Ranger. The dash and the Zeus were completely different. Ended up being a bad temp sensor. Good call.
Biggest reason I remember it is my Subaru has 2 temp sensors right next to each other (both a bitch to get to) and they didn’t use the same one until 2006
My 06 Silverado overheats unless the A/C is on.
Coolant appears full, needle never moves if the A/C is on, even when towing in traffic.
I haven’t seen the fans come on without AC.
The truck coolant temp climbs above 220*F
No obvious codes/check engine light either.
Thanks for your advice!