Both fans on all the time

[odd boy]

Hi,

I have camaro 98, I swapped both heads then both fans r on all the time. I know that there is no relation between the swap and the fan but it seems like the mechanics did a grounding problem. Any help??

I made some trials, like shutting them off by the DVT and it worked. And the samething happened with the AC.

[joecar]

Check that the ECT sensor is connected and reading correctly.

[odd boy]

I did, it is working and ECT is below on set point

[ChipsByAl]

If DVT control can turn the fans off, then the PCM is in control. Make sure you don't have any codes setting, this could make the fans come on. Post up the tun file, something may show up.
Al

[odd boy]

here it is

Final.tun

[roy]

Are all the grounds on the back of the heads ? Any pending codes?

[odd boy]

IAT code and compressor clutch

[joecar]

Do this:
- remove the fan relays and see if the fans stop;
- if the fans stop, then faulty relay(s) or short circuit upstream of relays (causing relays to pull on).
- if fans continue, then short circuit downstream of relays.

[odd boy]

I did that before, when I remove them, fans stop!! I will check the circut

[roy]

Are both fans coming on the moment the car starts up or after a few minutes or after the A/C is engaged. Did you have any A/C work done or r/r a component. I am looking at the schematic and it is pretty straight forward. I am just wondering if it is an input that the PCM is reading incorrect.
The ones that I canthink of is:
ECT- exceeds 113'c fans come on
A/C pressure enable - pressure is greater than 275 psi fans come on

Also if you have fbody service shop manual, look on page 6-1123 for electrical cooling fan disc. It gives more info than Ican type.