where can I get an A/C relay?

[TCMdocs944]

Any good places to order these from?

Approx cost?

[TCMdocs944]

Haven't tried yet....always wondered about relay test and repair but can't seem to find any good info on it.

Can I test with an AA battery by placing on + and - then listening for a "click" ?

I also have the intermittent wiper relay that is bad. I would love to repair both.

Do they normally just require a re-solder?

[DumasDemon84]

There are about 5 of them on E-Bay right now.

[TCMdocs944]

Good shot....mine is an early though

I think I am going to pull it tonight, along with my int. wiper relay and put them on a bench...take apart and see what there is to see.

If any soldering appears to be the slightest bit bad I guess I will refresh the points. Can't hurt too much at this point seeing as it will take me several days at best to aquire a new one.

Guess I need to break out the ohm meter as well.

[TCMdocs944]

Found at paragon..$43...ouch

[TCMdocs944]

Wiper relay $43 from paragon also....double ouch.

[mike944]

make sure you order the right part! the factory documentation is wrong on early 944's. They have the fan relay and the AC relay mixed-up.

Read the 4th post down for an explanation.

cooling fan relay

Do a search on "fan relay" and my username "mike944" for plenty of explanation

[TCMdocs944]

Mike - I do seem to remember that....my corrected relay diagrams are at home....thanks.


FR-- good info.

Anyone ever tell you that you should own a 928

[TCMdocs944]

Ok, so I pulled the relay (remember I have an 83) and it is the same part and PN as the rear defroster...switched them (no defrost ever in fl).


Nothing.

Here is something odd perhaps.

My relay (a/c and defroster) have audi/vw stamps and
pn171 937 503 - four pins.




I Cooling fan
II Fuel pump
III Air conditioning system
IV Headlight washer system
V Not connected
VI Rear window defroster
VII Not connected
VIII Not connected
IX Horn (Fuse 16 Amp.)
X Intermittant windshield wiper
XI Turn signals
XII Not connected


Summary:

Fuses appear fine
Relay appears fine (no actual bench test yet just swap)
Both fans come on when a/c knob is turned on (confirms relay good?)
Temperature dial is on full cool - moving does nothing
When the A/c DOES come on (usually with first start-up) I hear the relay click. No click at other times.
It runs for one "on" cycle and shuts off never to return.




What now?
My first thought is the temp select switch??

[mike944]

has it ever worked properly?

Look at the relay board, and count the contacts inside the socket. If you have 6 contacts, you need a relay with 6 pins. 4 contacts, needs a 4-pin relay.

[mike944]

Just re-read your question. Seems like your relay is working fine.

It could be low on refregerant. there is a pressure switch in the low pressure return line. If the pressure drops below a preset point, the compressor diisconnects to protect itself. Too low a refregerant level means too low an oil level as well.

If you are positive the system is fully charged, it could be a bad pressure switch. The switch is located next to (or attached to, i can't remember) the reciever-dryer. Unplug the connector and jump this switch ONLY for testing. Look for bubbles in the sight glass on top of the reciever-dryer. if it now works properly, and you either see lots of bubbles, or don't see any liquid, you system is discharged, and that's your problem

[TCMdocs944]

Yeh, that is sounding good.

It is really an odd thing.

When it works, it works perfectly, no cycle on / cycle off as with typical low refridgerant.


Would this switch cause it not to come on at all...thing is sometimes it comes on with first start up. Other times it will just never come on at all....again, I am not hearing the familiar click(relay) just as the fan kicks in.

When it decides to work I start it up, turn it on, hear the click, feel the compressor pull and feel immediate cool.

odd