Manual Swap Wiring

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JFarhanbod
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Manual Swap Wiring

Post by JFarhanbod »

So I'm trying to finish up the electrical portion of my manual swap on my e24. Its an 88 so it had the electronic transmission which I understand has more wiring than others. (great..)

I'm pretty sure that I have the starter figured out, just splice the c200 to c101 at the start relay

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What I'm not really understanding the wiring for the reverse switch. Heres the diagram.

Image

What do I do for that? I dont have the reverse switch wires yet but I do have the actual switch on the trans.

Also would it be okay if I remove all of the auto stuff? Like the entire harness.

Thanks!
-Jason
88 635csi
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Brucey
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Post by Brucey »

Re the starter and reversing light wiring; just for a change it is easier to see what to do if you start looking at the wiring in reality rather than looking at diagrams.

There is a connector plug about 6" away from the gearstick. You can do everything you need to do there.

The reversing light switch goes in to two of the pins, and you just need a jumper across another two to make the starter permanently 'uninhibited'.

You can make the connections to the existing plug using bullet type crimp connectors IIRC; conveniently they are the right size to just push into the receptacles of the connector socket.

Personally I favour leaving the starter relay in place and functioning (which installing the jumper as per the above does). The reason for this is that although the current for the pull-in and hold coils passes though the ignition switch either way, the current is actually switched on by the relay. Switches are quite good at passing current but suffer wear and damage when switching inductive loads. I think the wear on the ignition switch is reduced if there is a relay present.

This would be somewhat academic if the ignition switch never wore out, but they do. I have an idea that they are more likely to wear out on manual gearbox cars (that don't have a start relay) than autobox cars, but I have no means of proving this; maybe we should have a poll?

Anyway if the starter relay suffers the wear instead it is a lot easier and cheapr to change this than the ignition switch.

Re the rest of the autobox wiring; provided the ends of the harness are taped up you can leave it be I think. There is little gain by removing it all and if there is the most remote possibility that you might ever want to convert back again then you may as well leave it.

cheers
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wattsmonkey
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Post by wattsmonkey »

Just like Brucey says, once you're looking at the reversing light wires you can't go wrong: you'll see the two wires leading up from the manual box and you'll see the same-coloured wires to plug the buggers in to.

I've left all the auto wiring connected up on my 635 now it's a manual, no problems at all, although it looks easy enough to remove the loom in its entirety when comparing a manual and an auto.
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JFarhanbod
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Post by JFarhanbod »

ahh that might be a pain since my buddy hacked off the connectors when we removed the auto shifter.. I'm sure I can figure out which wire goes where though.

I would really prefer to remove all of the auto harness though. If I were to do that, would I need to splice anything? If so, where? and If I remove the auto harness, where do the reverse wires go then?

I am removing all the cruise control stuff also. I'm trying to declutter the wiring a bit and knowing I have a dead automatic wiring harness there would bug the hell out of me haha
-Jason
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Brucey
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Post by Brucey »

JFarhanbod wrote:ahh that might be a pain since my buddy hacked off the connectors when we removed the auto shifter..
oops.... #-o
I'm sure I can figure out which wire goes where though.


yes, this isn't a French car where the wire colours don't mean jack...
If I remove the auto harness, where do the reverse wires go then?
along the wiring harness of despair, through the grommet of torment, and into the connector of mystery...? You'll just have to trace them out and see. The autobox wiring varies from the manual because of the indicator lights in the instrument cluster. It is a lot of work for little if any gain.
I am removing all the cruise control stuff also. I'm trying to declutter the wiring a bit and knowing I have a dead automatic wiring harness there would bug the hell out of me haha
it is something that many others have come to terms with; maybe you can too.

Do bear in mind that you presently have an accurate wiring diagram for the entire car. Making a couple of small changes is easy to take account of, but what you are suggesting may mean that you don't have a useful and accurate wiring diagram for your car afterwards. This could turn the car into a heap of junk at some point in the future; it may turn a simple electrical problem into an insoluble nightmare.

If you are going to strip out all the autobox and cruise stuff, I'd suggest that you try and make sure that you convert it to full manual spec, and where it varies, put permanent labels on the wires so that they can be understood later on.

BTW I keep looking at the wires to the DN123 lights and wondering if with a few switches etc I could make these work with the manual gearbox.

I think it might be quite jolly if the lamps were revised to read things like;

'warp factor' , 'retro rockets' etc etc :shock: :shock: :mrgreen: :mrgreen:

cheers
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Ralph in Socal
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Post by Ralph in Socal »

For your reference. Seems easy enough but Good Luck.

viewtopic.php?t=10505&


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JFarhanbod
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Post by JFarhanbod »

I saw that thread, It looks like he just removed everything which is what I want to do. I jumped the pins and started the car today so I know it works as is.

I still want to remove the entire harness since its so bulky and messy.
(for reference..)

http://i694.photobucket.com/albums/vv30 ... 010008.jpg

it looks like the relay I jumped is removed though (top left) not 100% sure though. I also found the wires for the reverse lights, theyre wrapped in the harness with the cig lighter, gonna see tomorrow if that gets them to work.
-Jason
88 635csi
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BlackBetty
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Post by BlackBetty »

I am in the middle of this myself, good timing. Quick question on the wiring,
Does the micro switch that goes on the clutch pedal just disconnect the cruise, or does it prevent start in gear as well?
Sorry to hyjack
Pete
1988 Black 635 csi, 130 k miles
JFarhanbod
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Post by JFarhanbod »

Just cruise. I ended up removing the entire auto harness and couldn't be happier. You're left with 1 blk/ylw wire and it plugs into the big block where you disconnect the blk wire. For the reverse lights, I made a harness from the original wires on the auto trans harness. Plugged it right into the plug grouped with the cig lighter.
-Jason
88 635csi
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isellfn
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Re: Manual Swap Wiring

Post by isellfn »

Hi guys, I just had my manual swap done and along with the backup lights not working, I’m wondering if there’s a solution to the lamp illuminated in the dash that is looking for the automatic transmission…88 635 now 5 speed. What a difference in driving feel. Still with the 3.91 open rear, so it’s a mover now. LSD is in the future
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