a/c diag help on ford focus

[steveo3002]

seems the a.c doesnt work , quick look at clutch not engaged and rad fan off

dash switch illuminates as it should

fuse good and power present at fuse

if i bridge the relay the clutch engages , swapping the relay doesnt

rad fan off

got a hunch its because fan isnt on , not really sure how to proceed

mk1 petrol focus

 

[mtt.tr]

Could be low on gas, they will often have low and high pressure switches

 

[steveo3002]

Could be low on gas, they will often have low and high pressure switches

would it at least try and turn on ? any way to find out diy wise

 

[hotponyshoes]

would it at least try and turn on ? any way to find out diy wise

Probably not. Most of them just shut down without any sort of error shown to the user.

If it's had a leak and has run out if gas you can find the filling ports under the bonnet, take the cover off and try pressing the pin in.
If it's empty you'll be able to press it down with a finger.

I'd get a cheap diagnostic lead and a copy of the workshop manual.
I know fault codes are not the answer to everything but they are an easy way to start diagnosis on a/c problems

 

[steveo3002]

ive got a scanner , doesnt show any codes for a/c

 

[daedalusminos]

If there's no gas, the condenser is the first place I'd look - susceptible to corrosion and damage. Probably about £50 for a replacement.

 

[steveo3002]

if the gas is okay and i poke the little valve for a quick psssst would that release too much

does it matter if its high or low valve?

 

[daedalusminos]

Go for the low valve... usually a standard Schrader

 

[steveo3002]

okay got a psst from the low valve

 

[hotponyshoes]

Try the high valve, you shouldn't be able to push that in with a finger

 

[hotponyshoes]

ive got a scanner , doesnt show any codes for a/c

Is that a generic obd scanner?
I expect you'll need a manafacture specific cable, like the equivalent of vagcom for vw

 

[steveo3002]

will have a look at high valve another day need to get under the car or headlight out for that

ive got forescan ...so a bit better than generic ebay jobbie but i doubt its dealer spec

high side...so shouldnt be able to push at all ...or able with a screwdriver or such?

 

[hotponyshoes]

Forescan should be able to access the accm, you'd be looking for an option like component status or live data
That should show the state of all the individual parts, ie if the ac switch was on or off etc.
If you can pull all those readings up it's normally easy to spot a problem.

 

[steveo3002]

righto will have another look , tbh im not great on it

would it create a dtc ? main thing im worried about will the cooling fan operate in traffic, if that works i can suss the a/c at my leisure

 

[Matrixx]

Most places will offer a re-gas , if they cant fill they will not charge, well kwik fit anyway, cheap way to get a vacuum test and a diagnosis, if there is a leak.

 

[voipio]

If the aircon compressor hasn't run for a while, then the internal pressure should have equalised, so both high and low side valves will have a similar pressure behind them. Get one of the refill adapters that screw onto the refrigerant cylinders have a pressure gauge on them, and will work even without a cylinder connected, so no need to buy a cylinder at this point, but make sure you get the correct adapter for your car. The system pressure will soon tell you whether the refrigerant level is low. Most recent cars will be charged with refrigerant R-1234yf, and need a different adapter to earlier models, which typically use R-134a, and older still systems might have R-12. There may be labels on the refrigerant pipes somewhere to tell you this. The other factor that the a/c uses is outside temperature. If it's below about 7 or 8degC, the system won't run. Some car a/c's will run at slightly lower outside temps, but not much lower.

 

[steveo3002]

right ive found these related to a/c not sure what button to press , should i be able to enable cooling fan from the scanner etc

 

[steveo3002]

isnt the outside temp , was getting sweaty the other day so thats how i found it wasnt working

 

[voipio]

When was the a/c system last recharged? They do leak very slowly, mostly past the compressor seals, and will work for typically 2 years before a recharge is necessary. An ultraviolet lamp can be used to check for leaks elsewhere in the system, particularly the condenser, which is prone to salt corrosion.

 

[steveo3002]

its been recharged in our ownership , has worked until very recently

i guess i can get a gauge , wanted to rule out elecs , cheap free fixes first