MFA.........................................Dead?

hi lads.
 my MFA has been playing up (no suprises) its been on but not making any sense.
 yesterday i disconnect the batt to work on the car and now the display has cleared all 2getha with nothing on it at all?
 HELP PLEASE

try pulling the fuse, checking and reseating

will do mate,
 dont spose you know the fuse number do you?

Off the top of my head it's either 2 or 3 on an 83 Gti

Try removing the two battery terminals,  then clean up all the metal connections up with wire wool and assemble. Make sure you leave no wires off!

ok will do,
 ive heard that the order in which you reconnect the batt terminals can make a difference? or is someone just trying to blow me up? :twisted:

It might have an impact on the MFA, but the main reason that you should connect/disconnect battery terminals in the right order, is to minimise the risk of a spark - batteries produce hydrogen gas when they are being charged (by a charger, or by the alternator, when the engine is running), and a spark at the terminal of a battery which has a build-up of hydrogen around it can cause the battery to explode (rare, but serious injuries have resulted when it happens).

The correct order for DISCONNECTING battery leads is NEG first, then POS

When RECONNECTING the leads, connect POS first, then NEG

Also with that sequence you will not create a spark by accidentally touching the car with the tool as the neg is not connected when messing with the POS

yeah, i know the correct way to do it, but as i said someone told me that doing it the other way round may help?
 had a play last night but still no sucess, it might have to conceed on this one? unless anyone knows of a magical fix!

This may be useful to someone - I found a broken wire that fixed the MFA on my '88 cabrio.  The wire is brown with a white stripe, and attaches to the rocker cover at the gearbox end.  It comes from the wire loom near the sensor wire that connects to the end of the cylinder head.  This wire is also the supply return for the dash insert.  The previous owner had cut the dash return wire and linked it to the earth point near the fuse board, but this left the MFA switch return unconnected.  Don't know why VW made the return at the rocker cover though.

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This isn't the earth lead on the right-rear rocker cover nut? If this is missing then all hell will break loose with your electrics! :twisted:

That's the one!  It did for some previous owner, they had chopped the return wire to the dash insert and spliced in a wire to the earth point by the fuses.  Maybe the last guy didn't know what the MFA button was for…
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