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MG MGF Technical - The MEMS power delay Circuit- FAO Carl

The MEMS delay circuit is a great find Carl- maybe we should name it the 'Carl-circuit'?

Anyway, what I want to know is what is its purpose in the 'F? Is it actually attached to anything in the MGF application?

Thanks for any info (and this reminds me that I need to get hold of the manual and electrical circuit diagram!)

Ta

Rob
Robert Bell


When studying electric circuit diagram the output from "main relay" gives +12V to ; VVC control valves (if fitted) , stepper motor , ignition coils, injectors and purge valve at coal canister. It is then up to MEMS to ground other side of above units to performe a closed circuit. To my knowledge only stepper motor seems to be involved before system "goes to rest".
IMO itīs this function of "main relay" thatīs used on MK II to enable delay for windows etc. Anyone seen new diagrams for MK II ?

Whats important when doing any alterations is to use simple diodes like 1N4001 and some shrink tubing to prevent any backcurrents . We only want to feed FROM "Brown-Pink" to "Light-Green" not the other way around !
Regards, Carl.
Carl

Carl,
I think the german fax machine needs input. <g>
----------
http://mgf.virtualave.net/inhalt.htm
http://mgf.virtualave.net/sb8.jpg
http://mgf.virtualave.net/sb9.jpg

is the basic data (MPI), is it ?

Test for ASCII Diode:
Brown Pink (NK)---I>I--- Light-Green

Carl, can you produce a little MAD (manual aided Design)
IMO a simple Relais (NO) and an additional fuse should be added and used to 'isolate' the delayed signal. (Switching a 'plus' wire.)

Cheers
Dieter
http://mgf.tech.here.de





Dieter


Hi all,

To answer Roberts question about the purpouse of this delay i had a browse thru "Test Book" this morning as i remember having seen something related to this !
It is as follows: Main work for the delay is to reset stepper motor so it is ready for next start . But why all those other things like purge valve ,injectors etc ??
Well "TestBook" tells it all ; There is a test procedure when one steps thru these things and simply LISTEN for the "Clicks" when each injector opens, purge valve opens etc. Also charge times of ignition coils are tested !
It is very informative to have enough time to thorougly go thru "Test Book" as this aid is really fantastic! Even better when able to open "Advanced Toolbox" and be able to tweak some parameters - all within safe limits = no need for expensive add on boxes. When reading stories here about what happens when faultfinding at dealers it seems to me that not enough time is spent digging into this tool!
Itīs not that complicated - just read and point on screen....

Regards, Carl.
Carl

Thanks Carl- that answers my question nicely.

Is the circuit live whilst the ignition is on?

The reason for this question is that I wonder whether putting a relay in the circuit could actually power the boot release- not to mention the electric windows... would avoid voltage drop related problems too.

Rob
Robert Bell

Carl

Am I right in thinking that "Testbook" runs on a PC? How does it connect to MEMS - serial port, special cable etc?

Sorry for all the questions, but I'm interested in exactly what it can do and how it does it :-)

Any info would be appreciated.

Cheers

Richard
http://www.mgfworld.co.uk
Richard Eaton

Richard,
Carl is a little handicaped (high feaver) :(
So let me try to add some comments from my knowledge:

>Am I right in thinking that "Testbook" runs on a PC? How does it connect to MEMS - serial port, special cable etc?

IMO you are right. Connection runs over a RS485 interface (no problem to adapt from RS232 to RS485) ;-) But several sensors ond its Analogue Signals are a problem. BTW I 'heard' that the SW is well protected by a UK company with a really common name :(
---------------

On Carls instructions. I knittled with 'hot needles' a webside of the fax that Carl sent and added the diagrams while you wrote here.
IMO it should work and be OK. (The instruction, not the webside... LOL)

I could not rest and wait :) WEBSIDE online <g>
Really under construction and not approved. Please comment any failures. (not on my (our) spelling, that is multilingual crap, Sorry!!)

http://home.t-online.de/home/dkoen/delay.htm

CU
Dieter
http://mgf.tech.here.de
Dieter

<g>
Carl sent additional text at 21:45. I'll add it online tomorrow.

CU
Dieter

Dieter

http://home.t-online.de/home/dkoen/delay.htm

Hi,
as promised, here the updated version.
added is Carls suggestion on above stated webside to use an existing front to rear cable of the aircondition wiring. But this only if no aircondition is installed.

Carl and I are sorry again about our poorly written english, We hope you do not bother this multilingual crap but enjoy it. Impovals are welcome :) I did my recently best and added several 'the' etc. but I know that 'my best' is not enough :o)
If someone likes to correct that all, go do it :)
(BTW, where is Tony ? our friendly 3rd party translator ? :)
Some more pictures will be added later.

An understandable extract of section 6.1 should IMO immidiately generated for Gregs FAQ !
( 6.1 Possible faults, MEMS related, empty battery after 14 days)

Thanks
Dieter
http://mgf.tech.here.de
-----------------
Sorry, here should be the text, but the BBS comments failures on posting :(
Dieter



Where is the RS485 connector on the car that Testbook
conects to?

-matt
M66 MAT
matt


Hi Matt,

Unfortunatly there is no direct RS 485 outlet . All is via one single wire and ground from resp. unit. (MEMS , ABS , EPAS etc.) All this is sampled together in "Diagnostic connector" For RHD You find that connector at relay /fuses in passenger footwell. Program itself is a mixture of 16 and 32 bit - really confusing - at present only accessable with "original" computer due to other interface problems.

Doubt that it will be that way for long - ongoing work at several places to enable some if not all access to DIY-ers.

Carl,
Carl

Good work and congratulations to both Dieter and Carl- practically everything one needs to know has been put together now on a single web page. :o)

Carl, Dieter- have either of you tested to see if this all works yet?

Potential worry I have over the current circuit design is that the parallel installation may short the intended function of the circuit when the windows/ boot lid circuits are completed. Perhaps a relay in series with the 'Carl circuit' to power the accessories would be a better idea?

Rob
Robert Bell

FAO Carl,
I did an update with fotos, just 5 minutes ago.

Now ready fo checks.

I did some measures too at the purge valve wire. My NK cable recently remains app 5 minutes on power ????!!!
May be it depends on how high the battery voltage is, may be not. I had just only app. 13 V (after charging the battery)

I called my dealer because of this. He promised to ask an MG-Technician for that.... if he gets thru in that confused BMW organisation.

More later...

Ehmmm.... I have an old problem, for new :
See new thread:
Ride hight dropped, HydraGas Unit again blown ?<argggg>..

CU
Dieter
Dieter


Hi all,

Yes , it works -but dont panic if delay is up to 6 -7 minutes when only performing ignition ON/OFF !!

Did have an interesting tech-talk with Rover engineer today about this . Canīt quote all he said but summary is : Some MEMS units - especially other Rover cars can have delay up to 8 minutes at certain times. NORMALLY time is between 30 sec. and 4 min. All very much depending on how much engine has been working.. Just ignition ON /OFF makes the "F" sour !! He (or she) wants a ride !
PS, mine instalation works fine, bootlid relay next on list. See Dieters /my notes about fitting that as well and precausions needed due to heavy currents involved in switching !

Regards, Carl ( almost free from flue now!)
Carl

All this sounds very interesting,
but about one year ago, we were discussing the features of a forthcoming "easy life kit" made by Led man Richard Eaton.
This project was ambitious with one shot up and down windows, auto window closure when switching the alarm on with the keyfob and other fancy features.
I'm sure lots of us would put an order on such a device, me included.
It could, of course, use that power delay provided by MEMS ...

Are you reading Richard ? ;)))

Fabrice
Fabrice

>Are you reading Richard ? ;)))

Fabrice,
:))
I think we all shall WRITE to him and fill his mailbox. :))

Back serious. Such job must not be done by only one person. MGF 'projects' grew from that little 'cigar lighter' up to more complex things. This one began with questions at this BBS and was thought on by Carl, with my painful Q-Engineers questions to him and my low level grafic and webside design skills.
Richards skills on consumptions and webdesign are much better. He will need time !!!, but I think Carl does not and I do not bother if he or someone else takes the knowledge and improves it to a really good Side.

The only thing I would really hate is copying things and further on professional usage. ;-(

That would be not fair against all the members of this BBS who helped with their questions and messages to 'develop' this little features.

CU
Dieter
PS. the 'power delay relay' is NOW under costruction .. wait for low level update... <grin>
Dieter

Hi,
just remember another more or less useful feature for the use of the delayed power off signal (added relay!!).

Torsten Ohms wrote that it could be nice to power the radio on that circuit :))

So the radio plays on for the known time after ignition key off.

dk
Dieter

Carl/Dieter

Good work, yet another excellent web page showing how to do more goodies to our F's :-)

Fabrice

I haven't forgotten about the "Easylife" kit but as Dieter has noticed, my time has been very limited this last year as I've been so busy with "real" work ;-)

The good news is that a couple of weeks before Christmas I felt bad about not doing anything with the Easylife project, and have enlisted the help of another F'er to work on the hardware and PCB layout.

So fingers crossed, it should be a reality within a couple of months :-)))

Cheers

Richard
http://www.mgfworld.co.uk
Richard Eaton

>>So fingers crossed, it should be a reality within a couple of months :-)))<<

Richard,
that's good news !
I'm happy to see the "project ELK" is still going on.

Happy snowboardin' 2000

Fabrice
(2 weeks left before Val Thorens)
Fabrice

>Am I right in thinking that "Testbook"
>runs on a PC?

At Luxembourg it's a 486SX portable PC (brand: Hewlett Packard), running MS Windows 3.1 and using standard ISO9660 CD-ROM in a caddy through dual external (SCSI?) cdrom drives. The Windows interface is hidden since the testbook interface (with touchscreen 640x480 lcd) never lets you out of the system. But from the buttons, fonts, icons and other objects you quickly see it's the very old Windows 3.1.

dogslow machine btw, even my dealer complains how slow it is ;-)

I think MGF CD is not copy protected, but I'm not sure. They are updated regularly.
Dirk Vael

Dirk,
>I think MGF CD is not copy protected, but I'm not sure.

No, it isn't. But copies must be down as 'whole track'.
The PC's speach version must be set to the fitting language. The CD's Drive letter must fit to the SW etc. etc.

;-)
-?-

Fabrice

You've got a good memory! Yep, I go boarding in less than two days now, two weeks in Lake Louise, Canada :-)))))

To say I can't wait is a bit of an understatement ;-)

The only downside is that I'll be F'less and will have some serious catching up to do when I get back (no, not just on this BBS, but with work too!)


Dirk

So does Testbook require a dedicated PC to work? How does it connect from the PC to the MGF?

I'm sure you realise where I'm coming from. If we were able to "acquire" a CD and make the appropriate cable, would we be able to setup any old PC to work correctly?

-?-

>The PC's speach version must be set to the fitting
>language. The CD's Drive letter must fit to the SW etc. etc.

So this must mean that there are different versions of testbook for different countries. And if the CD drive letter has to be specific, Rover must sell Testbook as a complete package with a laptop etc or they'd have loads of compatibilty problems. Unless of course there's a newer/different version of software that has all these things configurable - now that's the one we want, any offers? ;-)

Cheers

Richard
Richard Eaton

I was talking to someone about this a while ago. As you do ;o)

Yes, the whole thing is sold as a package. The laptop is standard fare, but rides on a specific interface box... I do not recall the details unfortunately.

I suggest you get friendly with your local service technician and ask to take a look for yourself Richard!

Enjoy the snow boarding!

Rob
Robert Bell

PC-MGF connection is a dead normal serial connection on the pc side and this custom connector which connects to the fusebox below the steering wheel.

I do rememeber dealer told me for real time monitoring of certain serious engine stuff (not stepper of standard test, I did them myself once at dealer, pretty easy) you needed to connect a different cable, which was not connected to the laptop but to the specific housing below.

And now I remember: the scsi cdrom drive is scsi :)
Dirk Vael


Hi all,

The transformation from MEMS "one-wire and ground only for RX /TX" outlet to RS232 for computer is very similar to a well known system used for interfacing ICOM amateur radios to computers. So circuit diagram is aviable, Hooked up to active MEMS shows 232-pattern signals on oscilloscope.
Really hard bit is current clamp interface and as Dirk mentioned Windows interfacing. I am no expert and never will be on software but some of the hardware stuff seems familiare. Remember - by todays standard this is old junk !! Have been told that online ISDN is on its way as allready in use by VOLVO.

Regards , Carl.
Carl

I take it we are talking about "testbook" by HP

http://www.hp.com/auto/electronics/diagnostics/flash/testbookwireless.html

Looks like it.

Regards,

Martin
Martin

There you go. Here's test book:

http://www.hp.com/auto/electronics/diagnostics/solutions/hpandrover.htm

regards,

Martin
Martin


Hi all,

Yes - thats the system. Very seldom nowadays one get a really good laugh ... I recomend everyone to read "Results / Benefits " at ..... /hpandrover.htm.

Regards , Carl. :)))
Carl

The Results / Benefits bit-

>>*Dealers found that customer retention was significantly improved by being able to achieve "right the first time" fixes.<<

We could be cynical here...

>>*Technicians found that fault-finding time was reduced by 20%. With the combination of diagnostics and context sensitive help, the need for off-site training was minimized.<<

No off site training??? No wonder no one can use the equipment! ;o)

>>*Customers were happy. Their cars were fixed quickly and correctly, and their choice of a Rover vehicle was reinforced as a smart one.<<

Er... Okay boys and girls, calm down now... ;o))

>>*Overall, the company was able to improve productivity and to build loyalty with their customers.<<

Oh goody. So when does this all start then? Oops... It has already?

Rob
Robert Bell

Yet others who reside on another planet!!

Rog
Roger Parker

Back on the subject of wiring wondow relay to 'NK - brown pink'

I have picked up NK from Purge valve and connected to 'blue yellow' a/c circuit behind MEMS.(Had to move mems mounting bracket to fin it due to slight difference on rhd cars)

But I can't find the 'other end' of blue/yellow'

Dieter/Carls guide at http://home.t-online.de/home/dkoen/delay.htm
says I will find a loose connector - for the a/c realy near fuse box.

Dieter - can you describe the connector, no' of wires etc.
The only ones I've seen have no blue/yellow cables - and I have looked under left and right hand foot wells

jt
John Thomas


Hi John,

Will be down in my garage tomorrow so will post number of cables and colours to that free connector.
On LHD cars it is in "our "drivers side footwell - just to the extreme left -. very close indeed to fuse and relay pack. Probably the connector is intended to mate with a "Relay module" that steers fans and compressor clutch when aircon. is mounted.

Will be back around noon tomorrow with more info,

Carl.
Carl


Hi all,
just returned from garage with following info; The connector in question is a white plastic 2-row connector with a total of 7 cables.
Colours on these are : Blue/Yellow , Blue / Grey , Blue / Red in one row. Blue / Black , Thick Red , Green / Grey and Blue /Green. And as said , on LHD cars it is hanging loose at the extreme left in left footwell. There might of course have been a change during VINīs to fit or not to fit these extra cables. Maybee only fitted on export cars??

Regarding us well-built (around 6 ft. and big feet ) there is considerable more space to be had if the plastic lid covering fuses /relays is cut down in size and only fastend with upper 2 screws..... Not visible when done and as said makes it far more easy to get in /out and generally reach brake pedal.

Regards, Carl.
Carl

Thanks Carl - just to let you know I'm still hunting for the thin blue/yellow wire on my RHD car.

It goes into the loom from the connector at the MEMs -it must come out somewhere.

Assuming it's destined for the a/c relay then the UK Workshop Manual's Heating a/c section shows the control relay to be located in LH footwell area so I've had a good poke around there but on RHD cars the only unused socket in that area looks clearly designed for the passenger air bag.

Poking around the thick bunch of cables in the loom that runs down LH side of RHD cars reveals two blue/yellow wires but of greater thickness than the one I'm after - and tests show they are not the right one.

Still puzzled - could anyone with full wiring diagrams shed any light on this eg:
check wiring to a/c relay and see if there are any comments like "LHD or a/c cars only" If this is the case perhaps look and see where else the thin blue/yellow from mems area might stop.

I realise the 'fallback' is to run another cable but I'd prefer not to if poss.

jt
John Thomas


Hi,
Did You have any sucsess in finding the cable ?

Just curious if there is a diff. between LHD and RHD
as none is reported in wiring diagram.

Regards , Carl.
Carl

Thanks for your efforts Carl.

I'd concentrated on LH side believing thats where they'd fit the a/c relay - no luck so far.

I haven't looked for past few days so I will re-double my search this weekend.

jt
John Thomas

OK, hopefully this is the end of the saga.

The blue/yellow coloured wire that I found was actually the one coming *from* MEMS and terminating at a connector plug behind the MEMS. The end of front to rear harness plugs into this connector but has no blue/yellow etc a/c cables.

I have no a/c wiring on my RHD 1.8i, this is I believe because I have no ABS and have a simpler harness. If you have ABS I think you may get the a/c wiring too.

In the end I took 5m wire and ran it from fuel puge valve down the RH side of the car following exactly the route taken by the bonnet release cable - it was extremely simple to do.

The cable and diodes came to 95p and I now have a couple of minutes worth of power to run the windows.

The trickiest bit was making the conncections near to the window lift relay due to lack of space - I used a strip of barrel connectors to simplify matters.

Many thanks Carl & Dieter for all your help.

jt
a10jst
John Thomas

John,
thankyou from my side for your exploring the non ABS version. This will prevent our friends from not useful 'surprises'
:)
I'll add this term to the webside.
Carl will be back at weekend.

Cheers
dk
PS ..'strip of barrel connectors' ? (barrel = Gewehrlauf or Tonne or Fass ?':-/
Dieter

Dieter
"a picture speaks ....

https://catalogue.maplin.co.uk/largepics/Pictures/13/6/25SH50E.JPG

john
John Thomas

boing ;-)

John, das ist eine Luesterklemme.

Barrel connector = Luesterklemme, ... Zzzz.
BTW both are silly expressions IMO.
A 'Luester' is the old german name for a 'lamp', (former with candles and in the 20th as electrical lamp')

Thanks
Dieter
PS never use barrel connectors in a car, better is a crimp connector. :)

Dieter

This thread was discussed between 03/01/2000 and 24/01/2000

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