mfd not workin properly

[bigdan1505]

hi just wondering if anyone knows how the mfd in the mk 3 gsi works ive got a phase 2 with a c20 xe fitted. The range goes up when your driving and is all over the place and the mpg dont work, its stuck on 99.9 :-( please can anyone help

[1374lee]

I ALSO HAVE A PHASE 2 GSI WITH A 2.0XE FITTED RECENTLY,MY OUTSIDE TEMP WORKS,but not much else.I think you have to have the ecu re programmed at a vauxhall dealership to get the mfd to work correctly.I need to get mine done aswell.

Thanks.Lee.

[bigdan1505]

yeh same er mate yeh my temp works but thats about it lol, oh right so more pennies to the dealer then.
i thought it was a sender in the tank or a sensor somewhere

cheers dan

[Dom]

The range works by using the pulse widths of the injectors (which are provided by the ecu) and the vehicle speed sensor. By calculating from these two you can work out your instant MPG and average MPG / MPH

Check there is a speed pulse to the blue/red wire at the back and also a pulse from the ECU for the injector width (can't remember which wire that is but I'm sure AndyK will be along soon). On most MFD / TID when you're driving, if you press and hold both buttons, they will briefly display the current speed - good place to start.

[bigdan1505]

thanks dom yeh the speed works if u reset it while your driving, blue/red at the back of where mate cheers

[Dom]

If the speed works when you reset it then its not the speed pulse - its either the injector pulse wire or the program in the MFD is so way off its not registering properly.

I can't be any more help than that I'm afraid bud.

[Andy K]

if the instant MPG is not working, you need to look at the wiring in the drivers footwell.

Either a red/white or brown/black wire needs connecting between the car and ecu loom (to the same colour wire), missed in the conversion.

[1374lee]

I hve an LCD clocks set up,would the same apply to my car?

Thanks.Lee.

[Andy K]

Yes if the instant MPG isn't working,

[1374lee]

Andy,nothing is working instant or constant mpg nor the speed.The only things that work is the stopwatch and the outside temp.Tried pressing the 2 control buttons together whilst driving and it don't work.
Having said that my mpg is working some shape,it's showing anything from 0.6 to 1 mpg..lol.

Thanks.Lee.

[Andy K]

I guess the LCD dash conversion has stopped the speed signal getting thru somehow.

I would have thought the MFD was driven off the ABS on a phase 2, but not by the sounds of it. Anyone confirm ???

[1374lee]

Andy,right then,there may be a reason why my speed on the mfd doesn't work.My abs sensors are only plugged in on the rear.Getting a pair for the front soon.Would this explain why the speed is not working?Waht about the constant and instant mpg?

Thanks.Lee.

[bigdan1505]

thanks everyone gonna have a look today

[1374lee]

Dan,sorry to interupt your thread but I have the same problem as you.Let us know how u get on today.

Thanks.Lee.

[Andy K]

Yeah get your front ABS sensors sorted first. See if it helps.

Instant MPG is as expected without a speed input.

[Violet]

Should have 0 or --- if it's not moving.

Black/brown at ECU is fuel signal - black/blue at speedo is fuel signal - blue/red is speed signal. Is the blue/red same signal at the clocks as the ECU?

[1374lee]

Ok got the constant mpg,speed etc working now on mine but the range is not working and I have an F displayed on the mfd screen, I assume this stands for fault?Anyone any ideas how to get the range working on the MFD?

Thanks.Lee.

[Andy K]

it doesn't like your digital dash.

[RobJenko]

just for info, my phase 2 sport (1.8 originally) stopped giving correct mpg, range, etc the day i swapped to a x20xev

[1374lee]

just for info, my phase 2 sport (1.8 originally) stopped giving correct mpg, range, etc the day i swapped to a x20xev

Rob,I went from a 2.0 xev to 2.0 xe.I wonder if my readouts are correct now or not as the case maybe?

Thanks.Lee.

[Dom]

Different ECU ? Does it have the pulse output for the injector pulse width connected ?

[RobJenko]

yep dom, different ecu's.

[1374lee]

I have a montronic 2.5 off an early mk3 astra gsi but the very early 2.xe engine out of an 1989 gte 16v astra?

Thanks.Lee.