Menu toggle

Aircon/Heater problem!

danmason

danmason

New member
Discovered last night that the aircon / heater fuse in my 944t had blown, so replaced it today with an identical 7.5A fuse. 5 mins later, it had blown again! Now, I tried out the Demist function, also the aircon (which currently needs charging) ; I don' t know at which point the fuse went because I only tried them for a couple of seconds each. Could I have blown the fuse just by messing around like this, or am I looking at an electrical problem that going to be horrendous to resolve? Can anyone offer me advice before I try the other spare fuse?

Thanks
Dan
 
First thing to do would be to replace the fuse with an ammeter, so you will at least know if it is taking more than 7.5 amps.
If so, then you do have a problem - may not be expensive, just time consuming.
If not, then it would seem that the fuses are the problem.

Not too much help, but it is a start.
 
I don' t have my list of fuses in front of me but IIRC (if I remember correctly) there are a number of items on that same fuse.

I know this because mine kept blowing when I first had my car. I traced it to the heated rear window. There are two tiny wires from the tailgate struts to the car, these get very brittle and corroded. New wires and bayonet clips stopped the problem.

Not saying yours is the same but worth a look.
 
I had the same problem too, except my bayonet fitting snapped off when I tried to clean the connectors! A new one sorted out the blown fuses.
 
Hi guys, thanks for the advice so far. I will try the rear window heater thing tonight (was too busy on the 924 at the weekend!). In case the bayonet fitting / wires are beyond repair, any idea where I can obtain replacements?

One thing I was able to ascertain at the weekend is that there is WAY more than 7.5A going through there. I couldn' t get an ammeter in there properly, so decided I could take a measurement across the two terminals of a fuse. I duly put in a higher rated fuse that I figured wouldn' t blow (20A) and.... you guessed it, it blew within about 5 secs of switching on the aircon.

This seems a ridiculously high current - should I be worried? [:eek:]
 
I have heard that the a/c has an electrostatic clutch on the compressor - I have heard people before talking about it failing - hasn' t happened to me so can' t give you anymore details but if the fuse is blowing when the a/c is switched on i would look there. Also switching on the A/C starts the second radiator fan this could also be worth investigating.
Good luck,
keep us informed,
Tony
 
UPDATE! Firstly, the rear window stuff checked out fine - all the wires are mint. I also found that the rear window heater is not affected by the problem - it works fine, and seems to be on a different fuse.

So, I guess it' s time to take a look at the compressor :rolleyes:
 
Following further investigation, it SEEMS the problem only occurs when the engine is warm. If I turn the aircon on when the engine is cold - it runs faultlessly. But it seems that once the engine warms up, turning on the aircon doesn' t work because the fuse is blowing! I say ' it seems' because I' m unclear how this problem could occur. Could it relate to the main radiator fan? The aircon fan is functioning normally. Or is the compressor overheating? I' m getting confused...[8|]
 
Amateur mechanic time [8D]

To rule out the main radiator fan somehow interfering with the fuse why not start the car from cold. Switch on the A/C and watch the second fan switch on automatically. Wait for the car to warm up and if your fuse blows when the main fan switches in then you at least know what it is.
 
You must log in or register to reply here.

Posts made and opinions expressed are those of the individual forum members

Use of the Forum is subject to the Terms and Conditions

Disclaimer

The opinions expressed on this site are not necessarily those of the Club, who shall have no liability in respect of them or the accuracy of the content. The Club assumes no responsibility for any effects arising from errors or omissions.

Porsche Club Great Britain gives no warranties, guarantees or assurances and makes no representations or recommendations regarding any goods or services advertised on this site. It is the responsibility of visitors to satisfy themselves that goods and/or services supplied by any advertiser are bona fide and in no instance can the Porsche Club Great Britain be held responsible.

When responding to advertisements please ensure that you satisfy yourself of any applicable call charges on numbers not prefixed by usual "landline" STD Codes. Information can be obtained from the operator or the white pages. Before giving out ANY information regarding cars, or any other items for sale, please satisfy yourself that any potential purchaser is bona fide.

Directors of the Board of Porsche Club GB, Club Office Staff, Register Secretaries and Regional Organisers are often requested by Club members to provide information on matters connected with their cars and other matters referred to in the Club Rules. Such information, advice and assistance provided by such persons is given in good faith and is based on the personal experience and knowledge of the individual concerned.

Neither Porsche Club GB, nor any of the aforementioned, shall be under any liability in respect of any such information, advice or assistance given to members. Members are advised to consult qualified specialists for information, advice and assistance on matters connected with their cars at all times.

Porsche
Lockton
Pirelli
Officially approved
Oracle Finance
WEX Esso
Collecting Cars
Archant Dialogue
Back
Top