E30 M3 wiring

[BigD]

Hi guys,

I'm going to help a friend do an S52 swap into his M3 racecar and specifically he wants me to make a wiring adapter for him the way I did for my eta. My question is, does anyone know for sure, whether or not the c101 on the M3 is the same as all the other E30s? And if not, what are the differences (or maybe a full pin chart if it's totally out to lunch, although my guess is they're the same).

Thanks!

[matt]

http://wedophones.com/BMWManualsLead.htm + the bentley (both of them, really, but the e36 one is more useful)

[Teaguer]

Or if you are lazy you can try PM'ing Jason89i as he's swapped his M3 and possibly more .

[FredK]

Please do not PM Dad (Jason89i). He is a curmudgeonly old man who if he hasn't had his prune juice, can get positively cantankerous. ;)

OK fine, he's not that old, but here's what he will say:

READ THE ETM, READ THE BENTLEY, AND MAKE A WIRING DIAGRAM YOURSELF. NO INTERNET DIAGRAM IS CORRECT.

There are early and late M3s that will differ slightly in the way they are wired up. Please consult the ETM to verify wire function. But for a late 87 build M3, this diagram should get you started:

[LINUS]

D-

I'm sitting on a Treehouse harness for this exact swap. I don't plan to use it, so let me know if you want it, or if your buddy does. It's brand new.

-B

[equate975]

Its the same as a regular e30, I did the swap, but I used a THR adapter.

[Jason89i]

.......... Please consult the ETM to verify wire function. ...........

the irony is killing me.

and if your going to "quote" me, use the actual text.....bottom of page......

http://www.r3vlimited.com/board/showthread.php?t=90133&highlight=wiring

well, from my experience, there are 3 different wiring configs. late 87, early 87 and the airbag cars. my 3/87 chassis wiring was different than any other e30 ive worked on. the k5/k7 unloaders had a different trigger wire. if i didnt "consult the ETM to verify wire function" (thats how to use a direct quote fred) then the starter would continually crank with the ignition in the "run" position. not sure when the chassis wiring changed, but its something to be aware of.

oh yea fred, check your e30m3 pin6. unlike the m20, the s14 had an integrated fuel pump / o2 relay. function is listed incorrectly.

.......... Please consult the ETM to verify wire function. ...........

oh, and your e36 pin 15 is incorrectly labeled. it does have something to do with the wipers (and power windows and starter and relays) but you missed the point.

.......... Please consult the ETM to verify wire function. ...........

in all seriousness dmitry, dive in. were here to help. i can help with what i can. wiring diagrams can be easy to understand. but, im not going to do your homework when your out playing.

if your scared about wiring, dont want to figure it out or just want to make it a painless swap.....buy the treehouse adapter. nice product, trouble free, great tech support.

cheers, jason

[FredK]

Haha, my quote was totally in jest! I was hoping to circumvent people PMing you to ask about wiring questions, when it'd be more helpful for all of us to discuss the wiring diagrams out in the open.

The wiring diagram is Rev Engineer's. I don't have an M3.

[Jason89i]

Haha, my quote was totally in jest! I was hoping to circumvent people PMing you to ask about wiring questions, when it'd be more helpful for all of us to discuss the wiring diagrams out in the open.

The wiring diagram is Rev Engineer's. I don't have an M3.

yea, i picked up on the wink. thanks for the intervention. i used to get 5-10 pm's a week. had to nip it in the bud. and i just couldnt help "poking holes" on another on line diagram. i just cant help myself. had another birthday, so i cant disagree with that "old guy" talk..... and your right, i havent had my prune juice. cheers, jason

[FredK]

Looking over the ETM, it seems E36 X20 pin 15 takes power off the 30h lug on the starter and supplies it to:

OBC / multifunction clock
Body electronics control module (ZKE M)
Wiper module
Integrated climate regulation control module

My best guess is that pin 15 is used to store user settings in these modules.

[BigD]

Damn, I was afraid of that. Thanks for the info guys, that's a great starting point.

B - I'm doing this as part of payment for the clutch he gave me... unless you wanna help a brother out and give it to me for free.

[Jason89i]

Looking over the ETM, it seems E36 X20 pin 15 takes power off the 30h lug on the starter and supplies it to:

OBC / multifunction clock
Body electronics control module (ZKE M)
Wiper module
Integrated climate regulation control module

My best guess is that pin 15 is used to store user settings in these modules.

yes, and no. this is a trickey one. it has the same function as the blk/grn wire on the later e30's. blk/grn (terminal 30h on the starter) is a ground (only when the ignition is NOT in the start position.) on most e30's, this wire grounds the k5/k7 relays allowing them to switch power to the body electronics. HOWEVER, when the starter in initialized, the starter also sends power to the blk/grn wire, canceling the ground for the k5/k7 relays, turning them off. so when you put the key in the "start" position, the k5/k7 relays will not send power to the body electronics. my 3/87 m3 did not have this wire. they used the yl/blk wire to cancel the k5/k7 relays. it caused havoc w/ the euro motor.

boy, im getting tired.....better get some more prune juice. cheers, jason

[FredK]

Well I guess the best thing to do first is to find out the production date of the car or the last 7 digits of the VIN.

[FredK]

my 3/87 m3 did not have this wire. they used the yl/blk wire to cancel the k5/k7 relays. it caused havoc w/ the euro motor.

I see what you mean now. It'd be pretty confusing to figure this out, because at C101 the early 87 and late 87 both have BLK/YEL at pin 18, except that the early 87 would have Starter 50 (BLK/YEL) hooked up to K5/K7, and late 87 would have Starter 30h (BLK/GRN) hooked up to K5/K7.

I guess there's no 30h on early 87s?

[Jason89i]

I guess there's no 30h on early 87s?

correct. jason