Hi guys,iam having aircon problem,I have plugged in gap iid tool and the fault 0x9 refrigerant pressure fault.has anybody any idea as to what that refers too,cheers pat

I don’t specifically know that fault code, but there is a known problem with a pressure valve/sensor mounted on the A/C compressor itself.

You can change the offending item, but you need to remove the compressor to gain the clearance. Once you’ve done that, it’s just a easy to replace the whole thing.

have you checked the gas pressure?

Refrigerant pressure can be misleading, especially on warm days, you need to recover the refrigerant and compare the amount to the specified charge amount.

It's a good place to start looking as no gas = no aircon

If there's no pressure then yes, if there's some pressure, it can and has led people to think it's not a lack of refrigerant (and therefore a leak) that's the problem.

Hi lads.i have put a can of stop leak in and a can of refrigerant,the gap iid tool says it has 40 bar of pressure

It's way too high, I'd suspect the sensor or the connection to the sensor - are you sure the reported measured value is reliable?

40 Bar (580 PSI) is a lot, even for a blocked system, I'm surprised the pressure relief valve isn't / hasn't operated. It does sound like some default value has been set, try disconnecting the sensor and re-read the value.

As a guide, with the aircon and engine off

Deg. C R134a PRESSURE (PSI)
0 30
10 45
15 55
20 70
25 80
30 100
35 115
40 130

Last edited by Phoenix on 9th Jun 2022 8:11pm. Edited 1 time in total

Blimey, that's 580psi, IIRC maximum should be somewhere near 160psi Pete

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Up to 250 PSI with the system running normally and an ambient of ~40 deg. C.

I will check again tomorrow,to see if the reading has went down any,

Hi lads I have checked again,it still says 40 bar on the iid tool,and still have refrigerant pressure fault 0x9 showing up,cheers pat

Also as soon as i turn urn aircon on,the fan kicks on right away,is that normal I can't remember if it done that before when it was working,cheers pat

It does sound like a faulty pressure sensor TBH, try disconnecting it and see what reading & DTC you get. The fan running constantly is because it sees the pressure as excessive and is trying to cool the refrigerant sufficiently to lower the pressure.

Thanks for the reply,I will try that tomorrow and see what happens,cheers pat