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T

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Discussion Starter #1
Hello Folks

First post here.

FES is giving me a low pressure switch error PO530 for my A/C.

It's been emptied, leak tested and refilled, but still got the same error, so it wasn't low on gas before.

I can activate the compressor clutch with FES also. It makes a few clicky clunky sounds when tested.

So........is there any way to bypass the pressure sensor to test ?
Also, where exactly is the sensor in a 2006 facelift 147 diesel ?

Thanks in advance
 
T

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Discussion Starter #2
So no way to test if the pressure switch is at fault other than swapping it out ?

That's a shame.

Cheers
 
M

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Discussion Starter #5 (Edited)
Does late 147's no have 3 or 5 wires on sensor rather than two? Which would he bridge if that's the case ;)
 

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On most car's I've seen, the pressure switch is mounted on the reciever/ dryer, it's a canister type device and its behind the fog light on my 156, all the reciever/ dryer is is a hollow canister with the ridgid pipe looping in then out with a silica gel pack at the bottom to catch the condensation.

The pressure switch is also a safety device for your A/C system, I would suggest buying a new pressure switch and regassing, no other way around it really.

Hope this helps
 

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my pressure switch as just failed making the cooling fans kick in on full speed as soon as i start the car. manged to find some on ebay for around £35. So untill it gets here ive unpluged it stopping the fans.
 
M

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Discussion Starter #9
Why regass? Pressure switch on valve so you shouldn't loose gas when changing ;)
 
T

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Discussion Starter #10
This is what I can see on my car. What's this part ?

 

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Thats the pressure switch. As far as I know, the A/C system has to be evacuated in order to replace this part, as it does read pressure directly
 

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no need to release the gas. its screwed onto a bicycle style valve so no gas will escape when removing or replacing it.
 
T

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Discussion Starter #13
OK so that's defo the switch. Cool :)

It only has 3 wires going to it, so obviously different from others I've seen pictured on here which appear to have 5 wires.

I've read (and seen pictures) of the valve which the switch screws into. However, they were all screwed into the canister, this is screwed into a pip. There is a 13mm (I think) nut under the pressure switch, so I'm hoping that is a valve.

Cheers
 
T

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Discussion Starter #15
Yep...that's the part on my car.

Ok...got the aircon working !!!!

Now it doesn't

One of the pins gave a resistance of just under 17ohms with A/C switched on (although not working) and the plug in the sensor. If I unplugged the sensor and measured the resistance...*click^ the clutch engaged, the fan started blowing and within a minute I had ice cold air in the car.

So I messed about a bit. Now I can't get the aircon to fire up. Fuse is ok so I think I may have buggered the relay.

So now I'm further away from fixing it :lol:
 
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Discussion Starter #16
Anyone have the testing procedure for the Pressure Switch on a Mito or 147 GTA ?

Apparently that's the same system as fitted to the 147 from Feb 2006 onwards.

Cheers
 
M

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Discussion Starter #17
So Basically anyone got elearn to check pressure switch test procedure and see if either 147gta or Mito have test details for switch as 17gta shows switch without dryer (so at least same arrangement) and Mito has 3 pin pressure switch ;(
 
T

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Discussion Starter #18
Ok....got the aircon to fire up again.

Took out all the aircon related fuses (3 of them), none burst, but gave them a clean and now I can get the system to fire up the same way as before.

Basically unplug the sensor, then while testing for resistance/continuity between one terminal (purple) on the plug and the battery earth, the compressor clicks in and the fan blows and within a few seconds the car is like a fridge inside. So the aircon certainly works, but something is stopping it from firing.

Still haven't located a wiring diagram to check properly. If the sensor is left plugged in when I check continuity, the compressor doesn't fire up.

So I'm thinking I may just splash the £40 on a new sensor and hope for the best.
 
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