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85' EA82T air con fan running when ignition switched to acc. and on?

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Hi guys, recently removed the radiator on my 85' EA82T wagon to backflush the radiator. Now that its been reinstalled, the air con fan runs when I turn the ignition around to accessory and on positions. I'm fairly sure it wasn't doing this before, and I've checked the plug for the fan and the aircon isn't on in the car.

 

Anyone have any idea what might be causing this?

There is a Small Pressure Switch (aside a Bigger one) on the A/C Line, if it has one (or Both) Connectors Loose or Disconnected, it will act just like you Described.

 

So, I Kindly suggest you to check all those electrical connections on the A/C Line and Fix them in Place if one (or More) became loose; then try the Ignition Switch again.

 

Kind Regards.

  • Author

Sorry, I'm not sure what you mean by aircon line. Are you talking about the actual piping to/from the aircon unit or a seperate loom for the aircon? :/

I mean the Piping (Line) that Goes and Comes from the Condenser with the A/C R-12 Gas Pressure...

 

Look Behind the Headlamp, a Little bit down; you'll Notice two Pressure Switches in that Line, The Big one is to avoid the A/C Compressor to Spin on Low Gas Pressure, and the Smaller one is to turn on / off the A/C Fan on EARLY EA82 models only.

 

Newer EA82's has the A/C Fan activated by the Relays that are under the Windshield's base at the Engine Bay... in Fact: Subaru sold a Rewiring kit (a couple of Male / Female connectors to place between the Stock Relays and the Stock Plugs) to make the Earlier (1985 / 1986) EA82 Models to activate the A/C Fan with the Relay Signal, Bypassing that in-line Pressure Switch.

 

Kind Regards.

  • Author

Sweet thanks, I'll check it out and let you know how I get on!

  • Author

So I just had a look, can see four plugs - two 2-wire and two 1-wire. All were fine with good contact, pulled them all apart and had light corrosion on all. Cleaned that up with some hot water, plugged back in, but still the same.

 

I can't see the actual pressure switches on the line though, only the connectors. Anyone have a photo/diagram of where they are?

But do you found the Line, isn't it? ... Just follow it 'till you find those Pressure Switches, Both looks like Temp sending Solenoids.

 

ALSO: if the Thermoswitch's line is disconnected and the Plug touches bare Metal, the Fan will stay on with ignition too.

 

The Thermoswitch is the one attached to the Radiator, it could have two different connection Designs: Twin Spades on the Thermoswitch itself or a Pig tail wire with connector on the End.

 

Look ~► Here for Mo' info.

 

Kind Regards.

  • Author

I'm following the line (behind the right hand headlight if you're looking from in front of the car) and its covered in rubber/foam from where it bends from the metal line from the compressor all the way down to where it disappears into the hole beside the radiator, nothing on it. Is this one the one you're talking about?

No, it must be the Other one on the Other side, let me Explain:

 

My Wagons are Left Hand Drive, so the A/C Line is Behind the Left Headlamp (Passenger's side here in America, Looking from the Front of the Car) on them, but here goes a Hint: The Pressure Switches are in the Line that Goes to the A/C Filter, that must be the Other Line.

 

(there are Two Lines, one is Low Pressure and the other one is High Pressure)

 

Look for the A/C Filter: its Shaped like a Dark Bottle with a Hole in the Top, which really is a "Glass "Window" that allows to watch for Bubbles on the A/C Gas + Oil Mixture.

 

Have you already checked for a Loose Thermoswitch wires Connector? ... Because it could be the Culprit too, as I Explained above.

 

Kind Regards.

Well... an Image Worth 1000 Words, so Here is an Old Pic I Found on my PC's Hard Disc Drive:

 

 

A-CSwitches.jpg

 

 

I Hope this can Help.

 

Kind Regards.

  • Author

Yeah, I think I might be due for a new thermoswitch, just took a look at it and someones put rubbish crimp terminals on it. Looks dodgy.

 

Can't find this glass viewing filter though. Heres a picture of my engine bay I took a while back - can you point me to it on there?

 

IMG_2173.jpg

 

The AC line with the red cap on it is the one that goes to the radiator dealie in front of the radiator - the other one seems to go back into the firewall.

Yeah, I think I might be due for a new thermoswitch, just took a look at it and someones put rubbish crimp terminals on it. Looks dodgy. ...

 

Well, if both Terminals have a Short Circuit, there is the Culprit for the A/C Fan to Stay On.

 

 

 

...Can't find this glass viewing filter though. Heres a picture of my engine bay I took a while back - can you point me to it on there? ...

 

Yes, but I'll Need a Wider Picture to Look at the inner Fenders, because your Subaru is Right Hand Drive and Mine is Left Hand Drive, so the Placement Might Differ.

 

So, in order to Properly Help you to Locate those Switches, Please Upload a Picture of the Complete Engine Bay.

 

 

 

...The AC line with the red cap on it is the one that goes to the radiator dealie in front of the radiator - the other one seems to go back into the firewall.

 

 

Very Kindly Let me Tell you that you're Followin' the A/C Lines that goes to the Compressor, while I Wrote that you must search for the Pressure Switches on the...

 

 

...Lines that Goes and Comes from the Condenser...

 

Look Behind the Headlamp, a Little bit down; you'll Notice two Pressure Switches in that Line...

 

So, Look at the Lines that goes to the CONDENSER, which Looks like another radiator and is placed in Front of the Radiator that you removed for Cleansing.

 

Look to my Previous Post, it has a Picture. :D

 

Kind Regards.

Edited by Loyale 2.7 Turbo
Mispelled Word, Fixed.

...Heres a picture of my engine bay I took a while back - can you point me to it on there? ...

 

...Yes, but I'll Need a Wider Picture to Look at the inner Fenders, because your Subaru is Right Hand Drive and Mine is Left Hand Drive, so the Placement Might Differ...

 

 

Well, Yes...

 

Placement is Different between RHD & LHD Subarus of the Same Model.

 

I searched on my PC's collection of Photos and Look what I've Found about the A/C Filter Placement:

 

(No one of this Photos belongs to my Subies, they are Downloaded from Internet)

 

 

 

Left Hand Drive, like my Subies:

 

100_1707.jpg

 

 

 

 

Right Hand Drive, Like Yours:

 

15cbt5d.jpg

 

 

 

Now I Understand why you haven't located the Switch...

 

 

On the Left hand Drive Subarus, the Switch is near the A/C Filter, as you can see in my Subie's Photo:

 

A-CSwitches.jpg

 

 

Maybe you can find it on your Subie, following the Lines that Comes & Goes from the A/C Filter.

 

Kind Regards.

Dumb question, but is the defrost on?

 

Defrost setting will run the compressor and the fan.

 

you could just pull the AC fan relay. Sounds like you may want to keep working ac though?

Short to ground at the thermoswitch on the radiator. Disconnect wire to diagnose.

Dumb question, but is the defrost on? ...

 

That is Not a Dumb Question, Usually we forget about the Basics, so its a Good Question.

 

The Thermoswitch is a Good point too, I've already stated that:

 

...ALSO: if the Thermoswitch's line is disconnected and the Plug touches bare Metal, the Fan will stay on with ignition too...

 

So, we'll Like to know if you Already Solved the Problem or Not.

 

Kind Regards.

  • Author

No luck so far. Going to try get a new thermo switch and try that one for size - think it's got something to do with that.

  • Author

I think this may have something to do with the problem...

 

P1000068.jpg

 

 

Then again, looking over at the filter, there is some wiring with two wires coming off it. Looks like earths or something, but could be to do with the old air-suspension setup (which has been replaced with conventional springs).

 

P1000083.jpg

P1000081.jpg

  • 2 weeks later...

Well... if both Spade Terminals on the ThermoSwitch touches each other, the A/C Fan will be ON with the Key in ON or ACC as you Described.

 

Any Progress? ... Did you changed the ThermoSwitch?

  • Author

Not yet, been away for a few days and haven't had a chance to pick a new one up. Did, however, take it for a drive last week, runs fine and doesn't seem to run hot (according to the gauge, after about 15 minutes for 60mph driving temp gauge sits at around the one quarter mark) so it's still working. Going away again this week so probably won't get anything done for a wee while, but will definitely keep you posted. :)

  • 4 months later...
  • Author

Thought I'd update this as I never actually fixed the problem. Ended up selling the car to a guy down south, who was an apprentice mechanic. He text me about halfway through his trip saying the car was overheating. Poor guy ended up nursing it home, and haven't heard from him since. Last EA82T I ever buy!

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