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Old 4th July 2019, 11:46   #1
macafee2
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Default How do I test this relay?

How do I test this relay?

The pins are numbered 1,4,2 across the top and then 5 in the middle and 3 at the bottom.

The cover I think is positioned correctly according to the pins of the relay.

thank you

macafee2
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Old 4th July 2019, 12:14   #2
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Place your multimeter on a low resistance range across pins 3 & 4. You will either get a reading of zero ohms or infinite resistance.

Now place 12v across pins 1 & 2. The reading on the meter should change to the opposite state. In other words, if you got zero ohms to begin with, after application of the 12v you should see infinite resistance.

Simon
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Old 4th July 2019, 12:17   #3
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Originally Posted by SD1too View Post
Place your multimeter on a low resistance range across pins 3 & 4. You will either get a reading of zero ohms or infinite resistance.

Now place 12v across pins 1 & 2. The reading on the meter should change to the opposite state. In other words, if you got zero ohms to begin with, after application of the 12v you should see infinite resistance.

Simon
I'll give it a go, thank you

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Old 4th July 2019, 14:11   #4
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Quote:
Originally Posted by SD1too View Post
Place your multimeter on a low resistance range across pins 3 & 4. You will either get a reading of zero ohms or infinite resistance.

Now place 12v across pins 1 & 2. The reading on the meter should change to the opposite state. In other words, if you got zero ohms to begin with, after application of the 12v you should see infinite resistance.

Simon
Simon,
I have tested the relay that was in the car and a spare and both act the way you describe. I have to say now I have looked at it, I struggle with the relay being stuck but as I don't know and a mechanic says it was stuck, I don't really know what to think.

I'll fit the spare relay, use the car at the weekend and go back to the dealer making sure they have UV or what ever to detect the dye.

As a main dealer, rightly or wrongly I have blind faith they are true an honest.

thank you for the advice

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Old 4th July 2019, 17:08   #5
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I have tested the relay that was in the car and a spare and both act the way you describe.
Well there you go Ian, the "stuck" relay wasn't stuck after all!
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As a main dealer, rightly or wrongly I have blind faith they are true an honest.
So do most people. "Blind faith" can lead the innocent astray. The legal profession's maxim is safer and a lot cheaper: caveat emptor, "let the buyer beware".
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I'll fit the spare relay ... and go back to the dealer ..
I wouldn't do either of those things Ian. The original relay is fine so leave it alone. Don't introduce another potential source of trouble. Secondly, you're going back to a business which has demonstrated incompetence and giving them the opportunity to charge you for more misdiagnoses?

My advice remains the same. For air conditioning, seek a self-employed sole trader or small business which specialises in it. But did you use your air con. much between April and now? Was in it use over the winter? You may well just be looking at refrigerant loss due to lack of use (the seals dry out and allow the high pressure gas to escape). Leave it switched on for a week or two and see if it consistently delivers cold air. If not, then you should have some dye to look for!
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thank you for the advice
It's a pleasure to be of some assistance Ian.

Simon
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Old 4th July 2019, 18:18   #6
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Well there you go Ian, the "stuck" relay wasn't stuck after all!

So do most people. "Blind faith" can lead the innocent astray. The legal profession's maxim is safer and a lot cheaper: caveat emptor, "let the buyer beware".

I wouldn't do either of those things Ian. The original relay is fine so leave it alone. Don't introduce another potential source of trouble. Secondly, you're going back to a business which has demonstrated incompetence and giving them the opportunity to charge you for more misdiagnoses?

My advice remains the same. For air conditioning, seek a self-employed sole trader or small business which specialises in it. But did you use your air con. much between April and now? Was in it use over the winter? You may well just be looking at refrigerant loss due to lack of use (the seals dry out and allow the high pressure gas to escape). Leave it switched on for a week or two and see if it consistently delivers cold air. If not, then you should have some dye to look for!

It's a pleasure to be of some assistance Ian.

Simon
Simon, defiantly used it over winter and it does run most of the time I us the car.


When I had the car re-gassed a few years ago this was indeed the problem, lack of gas.

I'll see what the weekend brings. I did not use the air con on the way home today in case the relay was faulty but i live and learn

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Old 5th July 2019, 15:14   #7
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Every two years for a/c service is the general rule. Chris.S.
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Old 5th July 2019, 16:49   #8
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Every two years for a/c service is the general rule. Chris.S.
My car is 16 years old this December and has the original contents in the system. It works perfectly and has never been serviced. Should I start to panic ????----
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Old 5th July 2019, 19:51   #9
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My car is 16 years old this December and has the original contents in the system. It works perfectly and has never been serviced. Should I start to panic ????----
In a word John........NO** !!

Brian


































** According to the resident armchair expert you should now be rushing around seeking your local independent air conditioning expert, this of course is completely unnecessary
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