Hi,
I'm trying to repair the air conditioning in my 1993 940 Turbo, but it's taking a while and the summer heat is here.
The 940's radiator fan is electric and won't switch ON if the A/C is broken, so...
how do I re-wire it so that it will turn on when the engine starts overheating?
Any ideas?

I agree with Gus about not needing AC for fan operation, but don't think the ECT sensor he shows is relevant in fan operation.

My '93 Regina's AC is probably like yours, and my Fan relay is energized (High speed) directly by the radiator sensor, OR for High or Low speed by the AC system, with speed depending on system pressures.

--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

Hi,

I don't think you have to rewire your car, if the fan is not running you may have a problem with the fan or the coolant sensor. My car is a 94 non turbo with a broken air conditioner and the fan runs perfectly.

It should look like this:



Gus

I second what gus says. My 93 940 fan works just fine off the radiator switch and the AC has been broken for 5 or 6 years.

Thanks for the responses!

Just to be clear, one of the a/c hoses has been missing for years, so there's obviously no refrigerant in the system.

And I never hear the e-fan running after I park the car. I live in Portland, Oregon, so it's not super hot, but shouldn't it turn on sometimes???

What I thought I understood from the FAQs section and other postings is: no refrigerant=no efan operation, but it sounds like I just need to check the fan and the radiator switch, to see if those are both working correctly.

Could someone please tell me the procedure for testing these parts?

I live in Cal and go to and from the Bay Area to the MT., Lake Tahoe and anyone that know's the valley-Sacto. it gets HOT highs in da 107' so with now the A/C out no work..the "fan" did not work so the only thing to do with out fixing the A/C was to fix the "fan" connected to a switch that can come on with-temp from the eng. or manually a flick of the switch. It's handy in idle traffic when HOT! keeps the "turbo" cool to when park after a long trip at stop. Need to fix that A/C tho...NOW, why do Volvo have a wired A/C system....??

1994 grn wagon 940Turbo USA, CAL model.

Hi,

My radiator fan will only run if the motor is hot and the key is in the run position. Your fan may be quiet enough that you don't hear it run.

Gus

"I just need to check the fan and the radiator switch, to see if those are both working correctly.

Could someone please tell me the procedure for testing these parts?"

Easy...
Just pull back the insulation and short/bridge across the 2 thermo-switch terminals.

If you hear the relay click but get no fan action. it could be either the relay or the fan.

--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

I'm sorry, but I don't quite understand...

Am I bridging between two wires that go into the relay?

And is this the relay that is in front of the battery?

"Am I bridging between two wires that go into the relay?

And is this the relay that is in front of the battery?

The idea is to imitate a temp sensing switch the is closed, by making a connection between the 2 wires. One wire comes from the Fan relay coil—always powered and "looking" for a ground. The other wire connects to a ground point that will energize the relay.

Yes, on my '93 Regina, the Fan relay is in front of the battery.


--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.