The Rabbit TDI Project Part 10: MFA and cruise control
or: love of numbers, lazy foot.
The instrument cluster I purchased isn't available in North America,
it had to be imported from Germany. Actually, it came the long way.
I'm in Canada, I got it from a guy in the USA, who imported it from a
dealer in the UK, who had to special order it from Germany.
The long and the short of it is that I have it now.
It's an MFA cluster for a TDI.
For those who don't know, the MFA stands for something in German,
and loosly translated it becomes 'multi-function analyzer' or something.
It splits the center section of the cluster in half, and on the bottom half
displays outside temperature, and a selectable display for trip distance, time,
average speed, and average economy. It also can display instantaneous economy.
There are buttons on the wiper stalk for changing the display or resetting the
The MFA certainly becomes a watchdog for how you're driving.
Since my truck is an A1, I couldn't just swap in the signal and wiper stalks from
an A4 car in. And besides, they would just look wrong.
However, the Sciroccos were awarded their own version of the MFA computer way
back when. I actually have one installed in my 84 GLI which came from an 85
Scirocco. For the trivia buffs, the MFA was first available in the GTI in 1983, but not in North America.
(sorry for the quality of the picture)
Cut to the chase: I used the wiper stalk from an MFA Scirocco and wired it up to
operate the 2002 MFA. All of the functionality is not there, however, as the A4
cars can navigate up or down thru the display, and I can only go one way. No real
I also used a cruise control turn signal stalk from a so equipped scirocco.
It is wired up to operate the cruise control.
I was originally quite worried that I wouldn't be able to get the cruise control
to work, as I don't have ABS, and was expecting the ECU to want feedback from
the ABS system as a failsafe. As it stands, the ECU has a DTC because it's missing
the ABS controller, but the cruise is working fine.
On the A4 TDI cars, the cruise control in integral to the ECU. As some of our
European friends have found out, if you purchase a low end TDI car, it doesn't
come with cruise. Purchase and plug in the correct signal stalk, enable the ECU for
cruise via the Vag-com, and you now have cruise control.
Wiring for cruise was a little more involved. There are pedal switches required for
the clutch and the brake, as well as a feedback from the brake lights. I installed a
pedal cluster from a Cabriolet which had the old style cruise switches already
installed. The old style switches are already of the right variety (normally open or
normally closed, I can't remember). The brake light feedback came from the
brake light switch, also on the brake pedal. The only thing left was wiring the switch.
Wiring the switch was a bit more difficult, and I'm an absent minded idiot, so I
can't fully explain what I did.
'Course, I just looked thru my notes, so I can tell you exactly what I did.
On the factory A1 cruise switch, there are 4 wires.
I am wired as follows *:
Black to 12V
White to T121/14 and T121/46
Blue to T121/45
Red to T121/44.
T121 being the ECU wiring plug.
As it turns out, set is set, set is also coast.
on is on, off is off, resume is resume, resume is also accelerate.
The VAG-com is very useful, and a borrowed TDI also proved valuable.
Using the vag-com, Group 6 under engine, you can trouble shoot your
switches to be sure everything works.
Summary: cruise and MFA, technical type info
Part 1: Introduction
Part 2: Installing the Engine
Part 3: Transmission
Part 4: Wiring 1
Part 5: Speedometer and Cluster
Part 6: ImmobilizerIII
Part 7: Drive By Wire
Part 8: Intercooler
Part 9: Intake and Exhaust
part 10: MFA and Cruise Control
Part 11: The Dash
Part 12: The Little Things
Part 13: The End (for now)
Part 14: 6spd transmission and brake upgrades
One Year Later
Who Needs a VR6
Aug-28-2013 Edited for vBulletin/zeroforum changes
* disclaimer: If you do this and it fries your ECU, I'm not to blame.
This information is presented as a public service. Have your pets spayed
or neutered. Professional driver, closed course. Not all cars can be used
in some sets. When in charge, delegate. When in doubt, mumble. All your base,
are belong to us.
Modified by MrDave at 10:11 PM 4-25-2004