Radiator Fans running Continuously ! Relay Switch ?

[Zeppozen]

Hi,
Many threads on this but no search found an answer. I have an 1991 3SFE mk2.
Twin Radiator Fans.
No AC ( ever , I beleive)

So as its straining the Alternator I was thinking of a seperate relay switch to manually switch them on off.

Has anyone done this ? If so whats best and diagram please ?

Unless there is a simple solution I have missed .

Many Thanks

[pbmr2]

Could the fan switch in the rad have failed?

Maybe the fan relay is stuck?

In the frunk, there is a plug with a 'bung' in the end of it. This is a connector used to bridge the wires on the non-A/C cars. This could have come off. On the passenger side low down near the fuse box.
It's a long shot but easy to check.

[aussieGT]

So as its straining the Alternator I was thinking of a seperate relay switch to manually switch them on off.

Can't imagine it would 'strain' the alternator too much, it's designed for the job and Toyota nearly always over-engineers everything.

Maybe the plug has come undone near the radiators.

How would you monitor the heat to decide when to switch the fans on and off if you went manual? The heat gauge isn't that sensitive, tends to show 'hot' when its a bit late.

[thomp1983]

Has the car always done it or has the issue just started?

[2mad]

Has the car always done it or has the issue just started?

Good question ... for the record mine ran all the time . something to do with my intercooler fan i thought

[Zeppozen]

Could the fan switch in the rad have failed?

Maybe the fan relay is stuck?

In the frunk, there is a plug with a 'bung' in the end of it. This is a connector used to bridge the wires on the non-A/C cars. This could have come off. On the passenger side low down near the fuse box.
It's a long shot but easy to check.

Thanks I will take another look.

[Zeppozen]

Hi thank you for the replies.

Yes it has always had Rad Fans running ( both of them )

i put another radiator on a while back, it had another sensor in rad for fans...but still they were running ( could be same AC sensor)

My Old Alternators used to screech when starting car then stop after engine revved. ( usually a sign its on way out )

But for a New One to do it is worrying. Garage said that as both fans running plus power dip after starter it takes XX Watts load ...so over working it.

I have to change the Alternator annually. Either seizes due to tiny gap between rotor and casing corrodes. So put a rain cover over it.

Does anyone know which one and where the NON A/C sensor can be purchased for the Radiator ?

[Draven]

Hmm there is 100% no AC button in the car?

This normally happens if the AC unit is unpluged.

[thomp1983]

I've a non ac rad switch you can have, I'd suspect your car has had aircon in the past and it's missing the bridge link in the frunk that non ac cars have that prevent the fans running.

[Zeppozen]

Hi Thank you I will try that NON AC switch and at Least I know I have a "Known "

No AC controls or buttons in car.

But does have twin fans !

I checked and the connecter for the AC sensor and it has has a a wire looping / bridging it. ( just near the bulkhead in frunk.) at least hope thats it.

What I have noticed is that Fan 3 relay is missing ?
Do I need that ?

Thank you for help. If anyone else has any suggestions ...gratefully recieved