My First BMW – My First Swap – LS2/T56 into an E36

[motorV8ed]

I was under the impression that simple automotive relays are not polarity sensitive?

Probably you are largely correct. But there are at least some where they use a diode, so it matters:
IMG_7451b.jpg

I got that image from this page, which also says that most "Bosch-type" relays use a resistor: http://www.bcae1.com/relays.htm So probably I am just causing problems needlessly!

If I think of it, I will test one from my car tonight.

[motorV8ed]

In a development that surprises exactly no one, I tested all of the relays in my 1999 323, and none have diodes. I apologize for raising an inconsequential concern.

Carry on!

[TipsyMcStagger]

In a development that surprises exactly no one, I tested all of the relays in my 1999 323, and none have diodes. I apologize for raising an inconsequential concern.

Carry on!

No worries. Thanks for the follow-up.

Today was one of those days where I got completely frustrated and spent way too much time with something seemingly simple. It reminded me of the day I spent hours on my back upside down under the dashboard trying to remove the steering column fracture bolts. Or the day I ended up removing all of the rear interior to access and remove a single rivnut that had come loose under the package tray.

Today's frustration came when I decided I'd like to rewire the relay sockets. I like the way the relays clip to the fuse box. It makes for tidy packaging. So I consider it worth the effort to get it figured out.

I'd found only a single thread discussing removing relay terminals from the sockets. In that thread GC Allin described the process. I had just bought this cheap Chinese assortment of depin tools on Amazon. I read what GC Allin wrote but after hours of frustrating attempts, I just couldn't get it figured out. I finally decided to cut one of the sockets apart (it was a spare from the pick-and-pull) to remove a terminal for a closer look. After doing so, and being able to get a much better look at the "inside" of the socket, I had an Ah-ha! moment. After that, the process that GC Allin described made perfect sense.

You really need a third or fourth hand to do this but once you get it figured out, it's not so bad. Below are the two tools from the depin kit that I used. The fork gets inserted from above (after removing the white piece from the top of the socket). With the fork properly inserted, you have to then pull on the wire while at the same time, pressing on both sides of the cavity from the underside of the terminal.

I know a picture is worth a thousand words, and due to frustration and a lack of hands, I didn't take any. But after hours of frustration, once I had it figured out, I removed three terminals in under 10 minutes.

Tomorrow, I'll have to go to BMW to order new terminals.

Terminal removal kit from Amazon.


These are the two that I used to remove the relay socket terminals.


Victory is mine!

[bimerok]

Probably you are largely correct. But there are at least some where they use a diode, so it matters:
IMG_7451b.jpg

I got that image from this page, which also says that most "Bosch-type" relays use a resistor: http://www.bcae1.com/relays.htm So probably I am just causing problems needlessly!

If I think of it, I will test one from my car tonight.

MotorV8ed, you are correct, as your image shows there are Bosch style relays that have diodes in them and I did come across some that had those. However like you also noticed most of the time they are diode free in cars. So Brad, you should be fine using the feed from either pin 30 or 87 in a relay. Also electro-magnet is fine getting positive and negative from either pin 85 or 86. If for some reason you'll stumble upon relay that has a diode in it, it will not pass any current if you'll try to flow it backwards... Also most of the weird relays that I stumbled upon were with lights/fog lights and mostly in E30's.

Every single manual BMW has a clutch safety switch. It is not a thing starting in 1996.

I wouldn't be so categorical. It is far, far from all manual BMW's. E30 for sure did not have it. Also it is a thing on E36 that started in 1997. The ones that are 1996 and older do not have that. I just double checked and confirmed that all 3 of my 1996 e36's did not have a clutch safety switch to start the car.

[TipsyMcStagger]

...So Brad, you should be fine using the feed from either pin 30 or 87 in a relay. Also electro-magnet is fine getting positive and negative from either pin 85 or 86. If for some reason you'll stumble upon relay that has a diode in it, it will not pass any current if you'll try to flow it backwards... Also most of the weird relays that I stumbled upon were with lights/fog lights and mostly in E30's...

I have a bunch of these green 30A BMW relays I intend to use. The diagram on the relay definitely does not indicate a diode, so I'm good

Here's something random that I just now noticed, despite having had a relay socket in my hand for much of the day;

These green BMW relays are 5 pin. Yet many of these are used in sockets that are wired with just four pins. Hmmmmm? This relay was removed from the socket I depinned today. The socket had no center (87a) terminal.

[bimerok]

This type of relay should be good for you if you want to have 2 separate runs for something like injectors/coils for bank 1 and 2. You should be able to run separate branches from each pin 87 andadd your fuses on each line.

[TipsyMcStagger]

This type of relay should be good for you if you want to have 2 separate runs for something like injectors/coils for bank 1 and 2. You should be able to run separate branches from each pin 87 andadd your fuses on each line.

You know, I hadn't even thought of that. My understanding was that in a 5 pin relay, 87 is normally open and 87A is normally closed (or vice versa). But in looking at the diagram right there on the relay, it does appear that both 87 and 87A are energized at the same time.

I suppose it's easy enough to test. I'll just have to put 12V across the coil and check to see if both 87 and 87A are powered.

EDIT: Upon further research, this relay does in fact have two 87 posts (and no 87a post). It is a SPST relay that energizes both 87 posts when closed. Tested and verified in the garage today

[motorV8ed]

it does appear that both 87 and 87A are energized at the same time.

"This is my brother Darryl, and this is my other brother Darryl."

[TipsyMcStagger]

"This is my brother Darryl, and this is my other brother Darryl."

I get the Newhart reference. I guess it goes without saying that I'm old

[motorV8ed]

After I typed it, I suddenly feared that the youngsters on the forum would not get it. I also out myself as old!

[TipsyMcStagger]

...What I did in my swap is tied first relay to supply voltage for Coils and Fuel Injectors. ...

Hey Leo...EFIHarness posted on LS1Tech that they build their harnesses with all 8 injectors and coils on a single 15 amp fused circuit. He didn't specifically say what relay they use but one can assume 20A or greater.

So, you're on to something with they way you wired yours (minus the fuse)

That definitely simplifies things

[TipsyMcStagger]

...You really need a third or fourth hand to do this but once you get it figured out, it's not so bad. Below are the two tools from the depin kit that I used. The fork gets inserted from above (after removing the white piece from the top of the socket). With the fork properly inserted, you have to then pull on the wire while at the same time, pressing on both sides of the cavity from the underside of the terminal.


I know a picture is worth a thousand words, and due to frustration and a lack of hands, I didn't take any. But after hours of frustration, once I had it figured out, I removed three terminals in under 10 minutes.

I'm sure everyone has heard the definition of insanity is doing the same thing over and over again and expecting a different result? I don't want to admit how much time I've spent trying to remove these terminals from the relay sockets. It's maddeningly frustrating because I did it successfully the other day and seemingly know the procedure, yet repeated success has eluded me. My inability to accept failure resulted in many wasted hours. Finally and reluctantly, I accepted defeat and drove to BMW to order three relay sockets.


While at the pick-and-pull, I found this cool fuse block under the hood of an E46. It has this little fuse carrier that is an absolute bitch to open, but I don't think the fuse carrier is really necessary. With the fuse carrier removed, you can easily insert individual fuses into the block. There are five fuse locations in the block. Three are bused together. The other two are separate. The best part of this fuse block is that it is made to snap onto the tabs that retain the three E36 "external" relays. Neat!


So, I have a new plan. In the location of the original three external relays on the E36 main fuse box, I will have two of the mint-green (30A?) BMW (Siemens/Tyco) relays and this E46 fuse block. One relay will be dedicated to the fuel pump. On the other relay, I will use both 87 terminals to output to the E46 fuse block. I will then run the injectors, coils, MAF, O2 sensors and the reverse lockout solenoid through this relay. The injector and coils will be on one of the 87 posts, on a single 15A fuse. And the MAF/O2/Reverse will be on another 87 post on the same relay through a separate 15A fuse. I'm fairly confident that all of this can be combined through the single 30A relay without issue.


E46 Fuse Block


Fuse carrier removed


Fuse block without the carrier. You can insert individial fuses into the block.

[Tim Mc]

Tipsy - you have incredible persistence. I would have poked my eye out much time ago! You are paving the way for quite the comprehensive swap. Keep up the effort!

[TipsyMcStagger]

Tipsy - you have incredible persistence. I would have poked my eye out much time ago! You are paving the way for quite the comprehensive swap. Keep up the effort!

Thanks Tim. But what you view as persistence, I think of more as the protracted result of procrastination. I came across a great "engineering" term the other day that I think more aptly describes my less-than-perfect methodology; "paralysis by analysis."

Being that I'm doing many of these tasks for the first time, and that I get fixated on wanting to accomplish certain things a certain way, I have a huge reluctance to move forward and potentially make choices and decisions that might later prove to be less than ideal. My reluctance to make those choices often manifests itself in "paralysis by analysis."

I am motivated and although the pace will continue to be slow - given my travel and upcoming 4+ week cross-country motorcycle trip (Google/Youtube "Trans America Trail") - I will stick with it!

[motorV8ed]

Nice find. Thanks for the write-up. I wonder what the Teutonic purpose of the carrier/cover is?

[TipsyMcStagger]

I had a bit of an epiphany today regarding the unloader relay. There's some info in other threads about X20-21 controlling the unloader relay and some conflicting information about the location of the unloader relay.

Bear in mind I can't speak to anything other than the 1998 E36 but hopefully this will help someone else down the road;

The battery cable that brings power across the firewall from the B+ Jump Start Junction to the main underhood fuse box has a 14 GA wire crimped into the ring terminal along with the 8 GA cable. My 14 GA wire was long ago cut, so I wanted to figure out what it originally powered.

In looking at the ETK, it shows this originally went directly to the unloader relay. I started to get confused as to how I can have X20-21 run through the unloader relay if I clearly no longer have power feeding that relay, nor am I ever sure where it is!

So here's the Readers Digest version; the reason there is conflicting information about where the unloader relay is located is because there are TWO unloader relays. And the ETK refers to them both as "Unloader Realy, Terminal 15." One is K9 and the other is K6326. In my car, K9 is in the drivers footwell and it is associated with things like power seats and seat heaters, etc.

K6326 originally fed the coil packs on the BMW engine. It was an individual relay on a metal bracket located in the DME "cubby." This is the relay that I depinned the other day, always having been unsure about its original location and purpose.

So, X20-21 is simply switched 12V through the ignition switch. And you can activate whatever relay you wish to with X20-21. But in my case, the original "engine" unloader relay (K6326) is no longer a player and the 14 GA lead from the B+ Jump Start Junction can be reallocated as needed.

[motorV8ed]

The battery cable that brings power across the firewall from the B+ Jump Start Junction to the main underhood fuse box has a 14 GA wire crimped into the ring terminal along with the 4 GA cable. My 14 GA wire was long ago cut, so I wanted to figure out what it originally powered.

You may not be able to answer this, since your 14 GA wire was cut. But is it your sense that the 4 GA wire started at the B+ location, went over to the fusebox on the driver's side, where it was crimped together with the 14 GA wire, and then the 14 GA wire went back across the bay to the DME "cubby"? I am guessing that was how it was arranged, but it seems strange: why not just run a short 14 GA wire from the B+ location into the cubby?

In case anyone is wondering why I care, I am trying to figure out where to locate my fuel pump relay. Maybe that cable (for power) and area would be appropriate for it, since the LS fuel pump control from the PCM will be located close to there anyway.

[TipsyMcStagger]

You may not be able to answer this, since your 14 GA wire was cut. But is it your sense that the 4 GA wire started at the B+ location, went over to the fusebox on the driver's side, where it was crimped together with the 14 GA wire, and then the 14 GA wire went back across the bay to the DME "cubby"? I am guessing that was how it was arranged, but it seems strange: why not just run a short 14 GA wire from the B+ location into the cubby?

In case anyone is wondering why I care, I am trying to figure out where to locate my fuel pump relay. Maybe that cable (for power) and area would be appropriate for it, since the LS fuel pump control from the PCM will be located close to there anyway.

First a clarification; the cable that runs across the firewall is 8 ga, not 4 ga. The cables to the starter/alternator are 4 ga. I corrected my original post.

Attached below is the power distribution diagram from the ETK. The 8 ga cable has a 14 ga wire piggy-back crimped at the lug that connects to the B+ Jump Start Junction Point. This 14 ga wire ran directly to the unloader relay in the DME cubby, per the diagram (my green lines added to the diagram).

The other end of the 8 ga cable has a 12 ga wire piggy-back crimped to the lug that connects to the fuse box. This 12 ga wire ran directly to the secondary air pump relay.

I've decided I'm just going to make a new power feed cable from the B+ post to the fuse box. In all likelihood, I'll simply add a second ring terminal (lug) at the fuse box to which I'll crimp together two or three 12 or 14 ga wires, each of which will feed my relays and my small fuse block (the one from the E46).

[motorV8ed]

Hey, Tipsy! I hope you are well. I would love to hear an update on your project. And, if that is not in the cards, please know that the swap community misses you!

[bimerok]

Yeah tipsy! It’s been almost a year since we last heard from you.

[TipsyMcStagger]

Yeah, I'm still alive. I'll try to make a long story short; right after my last post, I spent the next few weeks of my at-home time (I travel for a living) prepping my KTM 450 XC-W for what was supposed to be an epic off-road coast-to-coast ride, known as the Trans America Trail, or TAT. We had a route planned leaving from Jacksonville, FL and were headed to Port Orford, Oregon.

We got underway at the end of July and I made it all the way to Day 2 of the ride before I made a dumb mistake and blew out my left ACL. End of trip. Two weeks later, I had ACL surgery. I was obviously out of commission for a while. I was able to return to my job in mid December. I was probably well enough to get back to working on the car in November but I left off at a really bad place. I was in the middle of wiring and I had/have wires everywhere.

I'll be honest guys, I'm at a major mental road block. I am sick that I've allowed this to drag on for a ridiculous amount of time but at this point, I have a mental hurdle that I can't get through. Every time I go out and look at that mess of wires, I feel overwhelmed and find something else to do. I constantly see build threads where people don't care about functioning A/C, or heat, or ABS or dash gauges, etc. etc. When all you care about is making the car move, it's a much more straight forward affair. But when you've set your goals high and are learning as you go, it's a different story. Or at least that's how I feel.

I have to leave town at the end of next week for several months of job related training. Obviously, that's not going to help.

I have gone out to the garage and tinkered a time or two and I have to say, if I had not kept up with this thread the way I had in the past, I'd be even more lost. I'll look at something and have no idea what it was I was trying to do and then I read my thread and it starts to make sense.

So, that's the story. Really embarrassed this is still a pile of parts in my garage. And thanks for "reaching out."

[bimerok]

Sucks to hear about the ACL injury and surgery and good to hear you are recovered from that.

As for the swap, just keep on plowing. You can’t give up. Just break it up in the smallest chunks possible and do small things at a time. It will move a lot quicker and you will be making positive progress

[motorV8ed]

Amen to Bimerok's sentiments!

I have just a coupla of thoughts I would like to share, if you will indulge me.

Wiring sucks. I was SOOO disgusted/embarrassed by how long it took me to get my pea-brain around it. And, by the way, I teach a damn college course on electronics (!) and the wiring stymied me for a long time. So don't be hard on yourself for that.

My next thought is not unrelated to Bimerok's sage advice to divide into smaller chunks. There is no law against getting it to move, and THEN getting some of the refinements done. I finished the season last year without A/C, and never having gotten my convertible top to work. I put the car to bed for the winter, and didn't even want to think about it. I cannot recall half the things I knew last summer. When I read my notes, I think that someone else must have written them. Well, guess what? After the winter, I am now working on the A/C, and I am excited about it again. At first I was not happy to restart the project, but now it is fun again.

Finally, let me comment on your thread itself. As you indicated, your documentation is helping you find your way back on track. What you may not know is you are helping OTHERS to find the path. It is my opinion is that a new swapper should start with YOUR thread, not with Braaap or Bimerok or Pzary or Tongboy or whomever. (No offense to them.) Your thread is gold: written after the pioneers blazed the path, and so well documented, so well written, and such high standards. It is very helpful.

Sorry about the ACL and the canceled coast-to-coast. No two ways about it -- that sucked. (I said "no two ways,", but... maybe there was an inattentive Donald Turnupseed waiting for you in Arkansas that you avoided?)

Now, good luck on your upcoming training. Afterwards, I hope you finish the beast, and am confident you can. But even if you decide that is not the path you want to take, I am similarly confident that the high-standard work you have done will serve you well in the future in some other domain.

[e36m3ls1]

Alternative thought here— get it running and driving and it might fuel your enthusiasm to do the less fun stuff. Gl

[TipsyMcStagger]

Thanks very much for the encouragement guys! I really appreciate it. And you're right; I can't quit and I don't intend to. I just need to find a way to re-motivate and move forward. Even if progress is slow, slow progress is better than no progress.

I'm sure you all have you own Covid stories but I started a master bed/bathroom renovation in February, knowing that I have to begin job related LTT (Long Term Training) at the end of May. I wanted the whole project done before I had to leave for training, so as to eliminate any outside distractions

Well, Coivid happened and six weeks ago the renovation stopped in its tracks when the tile guy refused to work. He finally decided to work again last week so once again (excuses) I'm racing to get this room put back together before leaving town next week.

At any rate, it's heartening know know you guys are in my corner and I'll be sure to update the thread once there's something to report!