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General => The garage => Topic started by: DropTop on 01 July 2003, 09:03

Title: MFA frozen
Post by: DropTop on 01 July 2003, 09:03
 ???
Just got my MK1 GTI cabrio last Friday. When I picked it up the MFA was fine, but after servicing the engine and pressure washing all the mud from under the wheel arches the MFA has stopped working.
If I disconnect and reconnect the battery the clock will work and I can change the time as normal, but as soon as I turn the ignition on the clock freezes, can't be adjusted and the MFA will not respond to the switch.
Seems like a short somewhere, any ideas?
Title: Re:MFA frozen
Post by: AdamB on 01 July 2003, 11:47
I had the same problem on mine, but it was resolved by pulling the fuse out, then replacing it.
Title: Re:MFA frozen
Post by: DropTop on 02 July 2003, 09:14
Tried that last night, but as I thought had the same effect as disconnecting the battery. Clock worked fine untill the ignition switched on then froze again.
Title: Re:MFA frozen
Post by: firefighter on 02 July 2003, 10:28
I had this problem on my mk2 & solved it by dissconecting the MFA cable at the switch & reconnecting it - hope it works.
Title: Re:MFA frozen
Post by: AdamB on 02 July 2003, 12:06
Now I think about it, that was the first thing that started to happen before my battery died on me. Check its a good battery. I know it sounds crazy, but you are drawing a lot of current when you turn it over, and the MFA could easily be effected.
Title: Re:MFA frozen
Post by: DropTop on 02 July 2003, 12:44
The battery is good. The MFA goes AWOL as soon as the ignition is switched on, before starting the engine.
Title: Re:MFA frozen
Post by: AdamB on 02 July 2003, 14:58
Without looking, it sounds like the live feed to the MFA is getting earthed when you turn the ignition on.
I think your best bet is to take the instrument pod out and check for any visual signs of a problem. If you know a little bit about car electrics you shouldn't have too much problem checking the inputs to the MFA. I have had my dash out a few times and there really is not much to it on the back.
Check the tracks on the printed circuit board on the back of the pod for any signs of overheating or shorting.
Its sounds like a job any half decent auto electrician should be able to figure out, but like I said, its hard to know without seeing it
Best of luck, and let me know if you do get it working.
Title: Re:MFA frozen
Post by: Bdub on 03 July 2003, 12:19
try a new ignition switch - only 7 quid, but can be a bugger to fit, if worn the contacts can make contact in the wrong places at the wrong time, I had a faulty one and the car would start, and when you released the key it just stopped.

worth a try if you've not where else to go!!!!
Title: Re:MFA frozen
Post by: DropTop on 03 July 2003, 12:59
I had that happen on my Audi Coupe GT a few years back. I don't think that is the problem here.
Title: Re:MFA frozen
Post by: tinman on 03 July 2003, 13:46
I'm throwing this up as a probably not, but anyway....

Is anything else on the car not working? Seriously, anything? This sounds daft, but check everything, in the three states the car has (off, ignition on, engine on).

I had a Golf that broke an earthing lead in the engine bay. Not easy to find in the end, but other things on the car went screwy at same time. For instance, the MFA dissappeared when i turned the head lights on, the engine spluttered if i did x, and so forth.

All down to one broken wire.

Justin
Title: Re:MFA frozen
Post by: DropTop on 03 July 2003, 13:52
Everything else seems OK. I checked and cleaned all the earth points in the engine bay (at least all the ones I could find).
The MFA has been given a low priority now as I need to replace the fuel pressure accumulator (on order  :-\ ) to get the car running again.