Rad Fan runs intermittently on high only when AC is on and truck is ironing or low speed.

[kneedragon76]

I searched and found a thread the other day that seemed to answers this problem but for the life of me I can’t find it now. It’s a 2016 EB and the radiator fan kicks on high for 10 seconds then shuts off for 30 then cycles like that any time you turn on the AC at idol or low speed. AC works fine the Radiator fan is just retarded.

 

[riphip]

They should all do that if AC is running... has to cool the 'freon' in the condenser coils since air is not flowing over condenser as it is while moving faster down the road. Otherwise your interior air would not be cool.

 

[kneedragon76]

It runs on high for 12 seconds then shut off for 20 then continues cycling like this. It started doing it last summer. This isn’t normal cycling and should not be high speed either.

 

[Kevin08]

If it’s more frequent than normal then your system might be low on refrigerant. The fan is coming on with the compressor and a compressor that’s coming on more often with short runs is low.

 

[00XTL]

Is the ac on max and what is the temperature outside?

 

[kneedragon76]

If it’s more frequent than normal then your system might be low on refrigerant. The fan is coming on with the compressor and a compressor that’s coming on more often with short runs is low.

I don’t have actual gauges but I thought it was short cycling at first put a can of refrigerant on it and it read normal. Is it possible the low side is too low?

 

[kneedragon76]

Is the ac on max and what is the temperature outside?

Like 50 degrees outside. It cycles like a dog in heat when you turn the AC on normal or max. As soon as you turn it off it rad fan stops and it runs perfectly normal.

 

[00XTL]

Ya. Definitely not normal. With the ac off do the fans operate at low speeds or normal speed?

 

[Utah Driver]

Might be over charged.

 

[OGBobbyJohnson]

Is it tuned? I have a 17 that was doing that when i tuned it. then i updated the tune online and it stopped.