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EDIS Wiring Questions
Posted: Mon Sep 09, 2013 7:26 pm
by pcf_mark
I am finally starting my MSII / v3.57 / relay board / Ford EDIS install. I am starting to build the wiring harness for the EDIS part of the system so I can run the spark side to start and transition to the fuel control. A few questions I have from carefully studying the diagram in the manual here
http://www.megamanual.com/ms2/EDIS.htm.
1) For the power side I am going to bring 12V through a fuse into pin 6 and take it off there to power each coil on post 2 of the coils. Is this ok or should I run a separate wire to power the coils?
2) The ground from the pin 10 - this looks like a basic ground I can run to the mounting screw for the module. Is this ok or should I run it back to the main ground for the rest of the wiring?
3) Coil grounds - is this through the mounting bolts to the bracket and then from the bracket to ground at whatever metal surface it is mounted on?
4) I was going to take a piece of speaker wire and strip it then wrap it around the VR wiring then terminate it at pin 7 on EDIS module. Is this ok?
5) I am using the wiring harness from DIY Autotune - are the PIP and SAW wires internally shielded or should I wrap a stripped wire around that pair also and terminate it at pin 7 on the EDIS module?
Sorry for the rudimentary questions but I want to do it right!
Thanks for your help.
Re: EDIS Wiring Questions
Posted: Mon Sep 09, 2013 11:56 pm
by trakkies
1) Single 12v wire (of adequate gauge) to the coils is fine.
2) Best practice is to run it to the MS ground point on the engine.
3) The coil metalwork doesn't have to be grounded for things to work, but again it's good practice to do so. Usually via the mounting bolts to the bracket which is fixed to the engine. The capacitor shown is often grounded via one of those mounting bolts.
4) Given the low cost, I'd use some proper twin screened cable. Can be bought from your MS dealer. I use a decent balanced microphone cable, since I already have lots of it.
5) Dunno what your loom has. If not screened, I'd use the same cable as above.
Re: EDIS Wiring Questions
Posted: Tue Sep 10, 2013 8:25 am
by pcf_mark
Thank you! I need to source some screened wire locally. Not sure if the Radio Shack technician will know what I want or need! I can always get it from DIY Autotune I think but I hate to order and ship just some wire.
Re: EDIS Wiring Questions
Posted: Tue Sep 10, 2013 2:41 pm
by trakkies
pcf_mark wrote:Thank you! I need to source some screened wire locally. Not sure if the Radio Shack technician will know what I want or need! I can always get it from DIY Autotune I think but I hate to order and ship just some wire.
I'm in the UK - but I'd expect RS to have it. Or a decent music store that sells mics, etc. But it must be for a balanced mic, ie twin screened, that normally uses an XLR connector. Things like guitars tend to be unbalanced and use co-ax.
Re: EDIS Wiring Questions
Posted: Tue Sep 10, 2013 5:51 pm
by pcf_mark
Will something like this work?
http://www.musiciansfriend.com/productD ... 0433648107
I could not find anything close on RS site.
Re: EDIS Wiring Questions
Posted: Wed Sep 11, 2013 2:41 am
by trakkies
That looks ok to me.
Re: EDIS Wiring Questions
Posted: Thu Sep 12, 2013 6:44 pm
by pcf_mark
I made a great score at Home Depot! 18/2 stranded, shielded wire for $.27 a foot. I hope the shielding is enough for our purposes. The actual shield is a little thinner than tin foil but the shield wire wrap is 18 gauge also. I soldered the ends for the VR on both ends and grounded the shield wire only at the EDIS module. I wrapped the last 6" on both ends with tin foil and taped it off so it is shielded end to end including the solder connections. I have to strip the harness for MegaSquirt and see if the PIP and SAW are shielded.
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 7:16 am
by kjones6039
Just curious...............
Is this solid wire? I would prefer stranded wire for automotive applications. Solid wire can be too prone to breakage among other things, IMO.
Ken
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 7:22 am
by pcf_mark
Yes it is stranded. It soldered nicely too. The shielding wire was a litte harder to solder but I am an amateur.
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 9:56 am
by trakkies
kjones6039 wrote:Just curious...............
Is this solid wire? I would prefer stranded wire for automotive applications. Solid wire can be too prone to breakage among other things, IMO.
Ken
I'd be surprised if Home Depot sold twin screened with solid cores - can't think of any use in the home. Or rather not a UK one.

Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 12:25 pm
by pcf_mark
Almost ready to mount everything. New wrinkle. The EDIS coils use a really odd plug wire end and of course my old wires are not even close. Does anyone make a new end I can fit on my existing wires? The Ford kit is $132!
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 3:20 pm
by trakkies
There are two types of EDIS coils. Both connectors are readily available new - the later type being cheaper.
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 6:45 pm
by kjones6039
trakkies wrote:kjones6039 wrote:Just curious...............
Is this solid wire? I would prefer stranded wire for automotive applications. Solid wire can be too prone to breakage among other things, IMO.
Ken
I'd be surprised if Home Depot sold twin screened with solid cores - can't think of any use in the home. Or rather not a UK one.

You're probably right, Dave. I was thinking that the most of the multi conductor wire I have seen was solid core, for thermostats and such. In fact I' not sure I have ever seen shielded wire at Home Depot.
Ken
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 7:32 pm
by pcf_mark
I am not sure if I should start a new thread or extend this one. My issues is fitting my trigger wheel to the engine. My balancer is small and the fit between the balancer and the water pump is very close. I bought a relatively thick (1/4") 36/1 wheel that is smaller in diameter than the balance. If I install on the front or the back the issue is that the ring is below the outer diameter of the balancer. Will this cause issues with the sensor picking up the signal with the balancer outer ring? I do not know how to post pics but here is a rudimentary sketch where the X part of the ring, balancer is the part made from line and V is where the sensor would be.
__
VI I
XI I
XI I
XI I
XI I
XI I
I_ I
Does anyone have a link to the new spark plug lead ends? I can buy new wires for $40 for aftermarket so maybe that makes more sense than $20 on new ends for old wires.
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 7:43 pm
by pcf_mark
The rudimentary image is not saving properly. Basically the sensor is next to the iron ring on the outer part of the balancer so it can reach the teeth on the ring.
Opinions?
Re: EDIS Wiring Questions
Posted: Fri Sep 13, 2013 9:15 pm
by kjones6039
pcf_mark wrote:If I install on the front or the back the issue is that the ring is below the outer diameter of the balancer. Will this cause issues with the sensor picking up the signal with the balancer outer ring?
It is
very doubtful that it will work that way. The teeth should extend beyond the balancer in order for the sensor to be able to 'see' them.
Ken
Re: EDIS Wiring Questions
Posted: Sat Sep 14, 2013 5:18 am
by trakkies
pcf_mark wrote:The rudimentary image is not saving properly. Basically the sensor is next to the iron ring on the outer part of the balancer so it can reach the teeth on the ring.
Opinions?
If you can get a standard sensor close enough to the toothed wheel and roughly central to it, you should be ok. Mine is mounted touching a pulley and with the teeth top only just protruding above.
Re: EDIS Wiring Questions
Posted: Tue Sep 17, 2013 7:08 pm
by pcf_mark
Ready to mount my sensor and set the reluctor ring.
In this page in the megamanual the direction of the arrow in the diagram is counter clockwise.
http://www.megamanual.com/ms2/EDIS.htm
In this page the arrow is going the other way
http://www.msextra.com/doc/ms3/edis.html
All said and done my question is engine at top dead center on number 1 cylinder. Looking at the front of the engine the balancer turns clockwise. With the sensor installed I should align the 5th tooth counter clockwise away from the missing tooth oriented with the sensor. Right? My ring can be rotated to help align it and I can lock it with a set screw.
Re: EDIS Wiring Questions
Posted: Wed Sep 18, 2013 6:45 am
by kjones6039
pcf_mark wrote:All said and done my question is engine at top dead center on number 1 cylinder. Looking at the front of the engine the balancer turns clockwise. With the sensor installed I should align the 5th tooth counter clockwise away from the missing tooth oriented with the sensor.
Assuming a V8, that would be correct......
Ken
Re: EDIS Wiring Questions
Posted: Wed Sep 18, 2013 7:36 pm
by kholman
If you are talking about the first picture on each of those pages, note that the first one (MS2 drawing) the wheel is viewed from behind while the MS3/Extra one is looking at front of crank.mounted wheel. ;)