I scanned my car and I have this error.

 

00819 - High Pressure Sensor (G65): Open or Short to Ground

 

http://wiki.ross-tech.com/wiki/index.php/00819

 

The cables look fine to me, assuming I am looking at the right part.

 

Is there anything I can test with a multimeter? 

 

I'm not sure if my AC is truly working. I had the compressor and condenser changed a couple of years ago, and it still feels pretty cold but at this time of year, it could be just fresh air blowing cold.

 

The part is cheap enough to just replace but access to get a spanner to undo looks tricky. 

 

Am I right in thinking that I can just undo it without having to regas as there is a valve under this switch?

Yes, you could check the 12V supply/earth to the sensor, if we can work out the wiring colours/pin numbers. Could be a blown fuse, but that supply is usually shared with other things so you'd probably have noticed more faults if it were the fuse.

 

Is it a climatic or climatronic system? What year is the car?  Might be quicker (than looking up wire info) to just measure voltage between each possible combination of pin pairs in the loom connector and see if you have 12V between at least one of the combinations with ignition on.

 

Yes, replacement is loss-less or almost so.

It's a 2005 elegance so has climatronic.

Black/grey wire on pin 3 should be 12V relative to brown wire on pin 1 with ignition on, I think. 12V looks like it comes from cabin fuse 4 (5A).

Easy to change, no regrigerant loss, try to find a stubby 17mm open ended spanner and do the job by feel.

 

Beware the cheap sensors on Ebay, it was a case of buy cheap buy 3 times for me

 

Yours will have failed from condensation build up rotting the crimped aluminium joint on the casing, in some cases you lose the regrigerant, in my case it hadn't.

 

I think if you hook up the new sensor and if its a good one you will get a reading of either zero bar or one bar on VCDS and not open/close circuit, if thats OK then swap it out, if you dont hear a little release of gas while unscrewing it and VCDS shows the same pressure when the new sensor reconnected then the old one (or another leak) will have allowed the gas to escape.

The wiring seems ok. 14v with the engine on.

 

Looking at the liquid refrigerant pressure on the climatronic it shows 51. Is that normal?

 

It has a compressor shut off code of 17 according to the climatronic.

 

 

17 = Compressor off (no signal or implausible signal from High Pressure Sensor -G65-)

All sorted.

 

New pressure switch fitted - £10 from eBay.

 

Best way to stop you losing a spanner into the engine bay should you drop it

 

Edited 21 March, 20197 yr by softscoop