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MG MGF Technical - Power Steering Cutting Out

Hi new to the site and was wondering if anybody could help me. I have a 1996 MGF VVC which has started to knock off the EPAS. The only way I can get it to come back on is to remove then replace the fuse. This has only started happening since I changed my clocks, (instrument dials), from Jap ones to UK spec ones, (Jap import). I have read about a safety cut out on these systems and was wondering if the sensor that sends the signal for this is situated on the clocks. Does anybody know? Also if it is on the clocks can it be changed or do I need a new set. The car is under warrenty still but the garage is 3 hours away from me. I took it to my local garage but they didn't have a clue!!! Any help would be much appreciated.

Thanks,
Lisa
Lisa

You are talking about changing the instrument pack from a Japanese spec one (in Kilometers) to a UK spec one (in Miles)?

Not having EPAS myself i don't know a great deal about it but i understand that it is speed sensitive and is supposed to shut off at a set speed. I assume that it takes this speed reading from the speedo cable (as it is the closest pick up point) and if so then this could be the source of your problem.

There are others on here who know a lot more about the car's electrics than i do (Will? Rob?) and i'm sure they will be along with a more definitive answer.

SF
Scarlet Fever

Hi, thanks for the reply. Yes it was the instrument pack from Japan that I swapped with a UK spec one. Ever since then the EPAS has been knocking itself off and will not come back on until the fuse is removed and then replaced, I guess this resets the system. It's not always ast the same point when it knocks itself off though. Can this be a dodgey sensor or a bad connection. Also the seatbelt warning light dose not light up on the UK instrument pack but does on my Jap spec one? I need help as it's driving me crazy!!

Thanks,
Lisa.
Lisa

Lisa

There is no seat belt warning light on the early UK spec *F*s so that is not a fault BUT I would think that the change of instruments has upset the EPAS sensors somewhere.

Question - who changed the instruments? You or the dealer?

Ted
Ted Newman

Sounds like the EPAS (power steering)control unit has lost its rev counter signal pick-up?

See http://www.mgfcar.de/schedules/sb33.jpg
and http://www.mgfcar.de/schedules/sb14.jpg
(thanks to dieter )

The EPAS needs a tachometer(rev counter) signal and a speed signal (from main MEMS control unit) and to work.

With luck its a broken or unmade connection near the revcounter.

Readers may recall very early threads that said if you idled the engine at a couple of thousand revs for some time you could cause the EPAS to diasble itself. This was 'cos the EPAS assumed from the rev counter that the car was being driven but without a speed reading it closed itself down.

Happy MotorinG
jt
John Thomas

Either that John, or the road speed signal from the instrument pack (pre-MY2000 MGFs with EPAS gets the road speed signal from the speedo: the mechanical instrument converts the movement of the needle to a signal that the EPAS can use).

Sounds rather like an intermittent contact or an inappropriate signal...
Rob Bell

I agree,

Sounds like a dodgy connector on the back of the instrument pack. My car is a 96 Jap import and was changed over to UK instrument before being sold to me. The seat belt warning sign lights up and the EPAS is as normal. The three wires, two for the EPAS signal from the speedo and the one for the Seat Belt Warning Light, all pass through the same connector housing on the back of the pack so it is probably this that's the problem. Possibly just needs reseating.

HTH

Bruce
Bruce Caldwell

Thanks very much for all the replys. Sounds like I will have to take the instruments off and see if there is a bad connection. It was my boyfriend who fitted it as the dealer sent me the instruments, (dealer long way from where I live!!). Will take it off tonight and see if I can find anything.

Thanks again,
Lisa
Lisa

Just had the instruments off and had a look at the connections, all seems OK. I put my old Jap instruments back in and the seat belt light comes on straight away, (it does not do this on the UK spec instruments). The power steering is fine when the Jap spec instruments are in. Could it be that the dealer has sent me an instrument pack that has a fault on it or do I need to do something else to make it compatible with my car? I seem to think it's a fault with the instrument pack because as Bruce says above the wires for the power steering and the seat belt warning light go through the same connecting block, but are OK on the Jap instruments.

Thanks,

Lisa
Lisa

Is it possible that a later edition instrument pack would not work properly with the earlier car?

I seem to remember that the speedo changed from analogue to digital - or am I getting mixed up with something else.

Also Lisa when you say the 'seat belt light' do you mean the warning for the seat belt not being worn or a faulty seat belt system BECAUSE the early models *F* did not have the former fitted on UK spec cars so obviously the panel will not show it either - or is my logic too logical!

Ted
Ted Newman

You may have something there Ted,
The later cars have an electronic speedo. If the new (to Lisa's car) UK instrument pack is the electronic type then it would have different connections. But then surely someone would have noticed that there was no mechanical connection for the speedo cable and hence no speed read out. I've just talked myself out of that one!! Oh well, while we wait for Lisa to return on that one I'll have a look at the connections on both models (new and old).

Look forward to meeting you on Sunday Ted, if you make it.

Bruce
Bruce Caldwell

Lisa, as you say, the fault seems likely to be in the instrument pack that you recieved from MG. It might simply be an oxidised contact on the circuit board - so it may be worth trying to clean it with a 'Contact cleaner' - such as that sold by Maplins.

Failing that - return to the supplying dealer, and try a replacement.

BTW UK cars don't have the seat belt warning system connected. Before Bruce mentioned that his actually worked, I was going to suggest that the speed signal connector may be wired differently - UNLESS Bruce's replacement instrument pack is different to the one you've been supplied with.

If anyone has access to EPC, perhaps they could check to see if there is more than one part number for mph marked instrument packs?

I'm sure I've seen disassembled instrument packs before (UK) and the seat belt warning lamp was not wired up... Some pix on Andy's site - but nothing that shows what I mean... http://www.sfforever.co.uk/showgallery.asp?queryon=16
Rob Bell

Hi,
not much help from my side.
There's a picture of a LHD km instrument pack
http://www.mgfcar.de/instruments/pack_cp_2365.jpg
I recall the yellow one in the centre contains the yellow-green wire from the speedo signal. (generated inside the instrument with a magnetic driven reed-relays contact)

This wire can be found as well at the connector on top of the fuse panel. We use it for GPS Sat-Navigation Systems.
http://www.mgfcar.de/navi/yellow_green_0120.jpg
All valid for pre MY2000 MGF of course.

Regards
Dieter
Dieter K.

Right latest update, first thanks again for all the replys, this is going to be a very helpful site!! My boyfriend has had a look at both clocks and noticed that there is a circit board which can be removed at the back of the instruments. This board has the power steering light, seatbelt light and the SRS light on it with a small yellow plug connected to it, (middle of instruments). He swapped this over, (Jap into UK), to see if it would make any difference as the Jap instruments do not switch off the EPAS. The only thing it did was to make the seatbelt light come on until you fastened it, (as it's meant to), I guess it's right then that the UK instruments don't have the seatbelt light wired up. The power steering still switched off after taking it for a test drive so I guess there is another signal off the instruments to the EPAS system. Is there any way of using the back of the Jap spec instruments, (the electronics), with the dials off the UK instrumennts. Or would this just mess everything up!! I think the only thing I can do now is to fit the Jap instruments and try to get another set of UK spec instruments. If anybody can find me a part number or serial number, (as there are numbers printed on the side), for one of these I would be very grateful.

Thanks,

Lisa
Lisa

Forgot to say they are both mechanical speedo's.

Thanks
Lisa

Nope, can only find 1 part number for mph instruments. Well, there are 2, but that is for early and late VIN numbers.

Johan
Johan Slagter

>I guess there is another signal off the instruments to the EPAS system.

http://www.mgfcar.de/instruments/pack_cp_2365.jpg

I recall the yellow one in the centre contains the yellow-green wire from the speedo signal. (generated inside the instrument with a magnetic driven reed-relays contact)

Just if you missed that ;)
Dieter K.

Lisa, this really is sounding like a fault with the replacement instrument pack. I don't suppose you have access to an oscilliscope? I suspect that the speed signal from the instrument is in the form of electrical pulses rather than a voltage/current... The problem may lie with those reed-switches that Dieter mentions.

Perhaps this module can be swapped from the Jap version to the UK one?
Rob Bell

>Perhaps this module can be swapped from the Jap version to the UK one?

It's a simple glas body with two contacts inside. (NO = normally open).
This can be changed by any cheap similar part from electronis parts shop. Only the size must be the same.
I'm afraid, but sold my old instrument pack. The buyer did this investigation and changed of the broken reed-switch then at his broken. So I've no own pictures.

The principals
http://www.arnoldmagnetics.com/corp/graphic/reed_switch.gif

One sample in the flash
http://www.mpja.com/pictures/11413.jpg

HTH
Dieter
Dieter K.

*g I forgot to say.
Signals at the MGF normally are pulled to ground by switches. Though I do not know the supplies for the reed-switch.
I assume it gets power (voltage) from the EPAS ECU.
Should be 5V then, as other signal power supplies with the engine ECU (regulated Power)


Dieter K.

Sorry, I should have mentioned that when they changed mine over they only changed the speedo unit not the whole pack! They presented me with the old speedo (in km/h) as proof of mileage covered so far. The old unit was given to me in the box that the new one came from. The part number of the new unit was YBC101120.

Perhaps you could take back the new pack and get it exchanged for just the speedo unit?

HTH

Bruce
Bruce Caldwell

Bruce, can you explaine a bit more on whet they swapped on your instruments. As I have both the original Jap instruments and a UK set of instruments is there any way I can combine the two to make one set of UK spec instruments that works, ie use the electronics off the Jap ones. I've had a look but can't find a way to remove just the clocks.

Thanks,

Lisa
Lisa

Lisa,

Not sure what you mean by both instruments but presume speedo and tacho. The speedo only was swapped on mine. They just removed the instrument pack, took it apart and replaced the speedo mechanics which included the dial, the oddometer and the reed relay which gives the signal for the EPAS. It all comes out as one unit. Contact me on mgfinbraunston@ -REMOVE-aol.com if you need a picture of what they removed, sending.

Bruce
Bruce Caldwell

Hi Lisa,
EPAS can kick out when battery start gettin old it needs a certain voltage which is 8.5v or something, if it drops below this voltage it disconnects hope this helps has happened to me changed battery and problem was gone
M L Dippenaar

Thanks to everybody who posted replys. Managed to get it sorted, (thanks to Bruce and his pics). Removed the UK speedo only and fitted it into the Jap clocks. Don't know why I didn't try that first!!

Thanks again,

Lisa
Lisa

Great news Lisa - glad to hear that all is now sorted :o)
Rob Bell

This thread was discussed between 11/08/2003 and 19/08/2003

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