DIY Full OBC Retrofit

[Zoso]

No 318 in the US ever came with the full OBC, but I've been enjoying one in my car for a few months now. It requires a bit of work and a special coding plug. As far as I know, I'm the only 318 owner to have done this.... for now :D

http://zoso.no-ip.org/318i-obc.html

OBC pages from owners manual (http://ee1394.com/bmw/docs/obc/obc_manual.zip) - 800k .zip
Interesting OBC tips (http://home.att.net/~ebaines/e28_obc.htm)

[Febi Guibo]

I followed this and am now the second (? -- i doubt it) 318 owner celebrating his car's high gas mileage. I got my coding plug at zionsville.

Also, for anyone interested, I have a OBC-compatible turn stalk, and the wiring, horn, and relay box for the CODE featuer for sale!

[m42 fan]

Febi-
How much were you looking to get for the parts? I've been trying to get things together for this for a little while now.

Zoso-
Many have said this before, but you're write-ups are first rate. Your OBC write up is what convinced me that this was doable.

Brian

[Febi Guibo]

+1 on that... it's a very doable retrofit... I did it when I swapped my dashboard and it made it even easier.

m42_fan ygpm.

[dude8383]

I followed this and am now the second (? -- i doubt it) 318 owner celebrating his car's high gas mileage. I got my coding plug at zionsville.


how much did you pay for that coding plug? i need to order mine cause i just bought a full obc for my car as well. Also what p/n is the coding plug...i wanna make sure that i will be ordering the same thing :)

[Zoso]

Many have said this before, but you're write-ups are first rate. Your OBC write up is what convinced me that this was doable.

Brian

Glad I could help! I always love seeing writeups on the internet - combined with the Bentley, I know what I'm getting into before starting something. So when I do a procedure, I just snap a few pictures and writeup it up. It's the least I can do to give back to the E30 community.

[Zoso]

how much did you pay for that coding plug? i need to order mine cause i just bought a full obc for my car as well. Also what p/n is the coding plug...i wanna make sure that i will be ordering the same thing :)


Part number is 65 81 1 394 111. Bavarian Autosport got it for me for... I can't remember exactly, but it was either $23 or $32.

[dude8383]

wow that much for a little tiny chip?! lol i thought i'd be like $5 bucks..w/e ill order mine sometime this week.

thanks!

[///Motorsport]

awesome write up!- the car i hope to buy has the OBC hanging out by a few wires so i assume i will need to do this..
thanks again

[Vladi]

I've fitted an OBC to my 316i about one year ago. My only problem is the AVMPG+RANGE which isn't correct because the codeplug is for a 325i, but i'm waiting for my M42 swap to order the iS codeplug.

[christophbmw]

Check out my OBC.....I'll do a writeup if anyone wants to know how to install one:
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wNzc2MjQ2NnM0MTNkZmQzMXk1NDE%3D.jpg
......got it off ebay for $12.

[Zoso]

It takes me too long to read that clock. I'd crash the car before I figured out the time.

[christophbmw]

It takes me too long to read that clock. I'd crash the car before I figured out the time.
......but it looks cool (you get used to it).

[m42 fan]

Well, I finally got this one done this weekend. Went just like Mike's writeups said. I excersised my better judgement and decided to forgo the code junk. Just a couple of observations:
1) I screwed up. While I was in there, I replaced all of the small bulbs in the cluster (including adding one for my now-present foglights). I didn't have the right bulbs for the two big amber ones that backlight the cluster at night. Well, you can guess what happened. I'll be going back in there sometime in the next month or so to put those bulbs in. Thankfully only the one on the tach side is out--for now.

2) If you don't have a 21mm socket when you go to take off the wheel, an O2 sensor socket will work.

3) When I took the car out for a test trive this afternoon, I noticed something interesting. The values the OBC was giving me don't quite match up with what the cluster is telling me. Example: I'll set the max speed function to 50 mph. the alarm will not go off till the speedo reads ~55 mph. Same at 30 mph. In addition, the mpg function was showing that I'm getting 27-28 mpg with 90% non highway driving. By hand, I have been calculating 22-23 mpg. --Note: I do have the correct coding plug installed.-- I'm going to assume that the OBC is giving me the correct info, and that the cluster is just off due to age or something like that unless someone on here has any better ideas.

Comments? Questions?

BTW, thanks for all the help with the write up, Mike.
Brian

[Febi Guibo]

Hey, as the E30 world's resident non-expert OBC go-to-guy... I added a link below zoso's writeup with some interesting tidbits about the obc (http://home.att.net/~ebaines/e28_obc.htm)...

I guess that tiny wheel... it's used to sync the OBC with exactly how much gas you have left in the tank. Kinda cool... who knew (obviously not me).

[Zoso]

Glad to hear you put my writeup to use! The retrofit really isn't that tough, is it?

The speed limit and the MPG have been right on for me.

Interesting about the speed limit. I have heard that BMW speedos can be off by a few percentages. The speed limit on my M3 is 140MPH, but it always kicks in at 136 or 137 :)

Regarding the MPG feature, try this. Get on a long flat road or highway and get it to 25MPG exactly on the dash then reset the computer and see how it matches. I'm curious if that'll match.

Do you have the stock cluster and the stock rear diff?

[m42 fan]

Yep, cluster stock, diff stock 4.10 posi.

I'm leaning toward the cluster being off. A few months ago as a test I reset the odometer as I passed a milepost on the highway. It wound up being off by 1/2-3/4 of a tenth every mile. I don't remember if it was reading high or low though.

I'm going to try the fuel economy test like you said, might be a couple of weeks though, since I'm riding my bike to school now that the weather has warmed up.

Brian

[Vladi]

The speed @ wich the OBC beeps is your real speed. The speedometer has a 10% error. (eg. @ 200km/h is actually 180km/h, 200 x 10/100=20km/h wich is you speedo error@200km/h)

[silverblades181]

The speed @ wich the OBC beeps is your real speed. The speedometer has a 10% error. (eg. @ 200km/h is actually 180km/h, 200 x 10/100=20km/h wich is you speedo error@200km/h)

I'd heard that BMW speedos were a bit optimistic but I always tought it wasn't more then 5 km/h...btw my car came with the 13 button OBC and I love it. L/100km is very useful, so is average speed and the speed limit for long trips.

[Vladi]

The optimism of the speedo depends on your tire size. ;)

[dude8383]

Part number is 65 81 1 394 111. Bavarian Autosport got it for me for... I can't remember exactly, but it was either $23 or $32.

ey mike, i finally got around to ordering the coding plug. BavAuto has em for $60 plus shipping..

Sooo i ordered from BMA. Cost me $52 shipped. Patrick is the man...

[Vladi]

In about two weeks i'm going to attempt to retrofit a full E36 OBC.(except the checkcontrol part which is a pain) :D
I've bought an E36 '94 M42 engine a month ago (to upgrade from my 316i) so i've practicly got the E36 electrics, ECU and everything. I'm 75% positive it will work. :D
I'll come back with detalis when it's done. ;)

[dude8383]

In about two weeks i'm going to attempt to retrofit a full E36 OBC.(except the checkcontrol part which is a pain) :D
I've bought an E36 '94 M42 engine a month ago (to upgrade from my 316i) so i've practicly got the E36 electrics, ECU and everything. I'm 75% positive it will work. :D
I'll come back with detalis when it's done. ;)

NICE! Come back soon lol...i was thinking about the compatibility issues but lets see how you manage!

[doigal]

In about two weeks i'm going to attempt to retrofit a full E36 OBC.(except the checkcontrol part which is a pain) :D
I've bought an E36 '94 M42 engine a month ago (to upgrade from my 316i) so i've practicly got the E36 electrics, ECU and everything. I'm 75% positive it will work. :D
I'll come back with detalis when it's done. ;)

About to do a simular engine swap in a couple of months time. Whats the advantage of the e36 obc?

[dude8383]

the e36 obc has more functions...

http://forums.bimmerforums.com/forum/attachment.php?attachmentid=156801&d=1150075977

[Vladi]

NICE! Come back soon lol...i was thinking about the compatibility issues but lets see how you manage!

Please do share your thoughts! Any comment/feedback is welcome. :)
Right now i'm thinking to replace my E30 instrument cluster with the E36 one. :D
The electrics isn't a problem, the physical part is the problem. I'm thniking of some sort of way to mould the E36 instrument cluster in the E30 dashboard.

[doigal]

Just a though - take the innards of the e36 and put them in the e30 case... might work!

[Vladi]

Ok, gave up on the E36 instrument cluster. :D
Anyway, i installed my E36 OBC in my E30 yesterday...YES, with my M40 engine and it all works accuretly! :D Wohooo!

[dude8383]

Ok, gave up on the E36 instrument cluster. :D
Anyway, i installed my E36 OBC in my E30 yesterday...YES, with my M40 engine and it all works accuretly! :D Wohooo!

PICS!!!

[Febi Guibo]

we need pics...

also, I think E46 gauges are the same diameter as ours, if that helps any (prolly doesn't, haha)

[Eurospec]

Anyway, i installed my E36 OBC in my E30 yesterday...YES, with my M40 engine and it all works accuretly! :D Wohooo!Way to go dude! New engine is in already?

[Vladi]

I'll take some pics today, the new engine isn't in, i hope to start the "process" at the end of the week. I still need the starter pinion. :( The OBC is mounted just for tests right now, it's in the final form. Anyway, i'll post some pics a bit later. :rolleyes:

[Vladi]

I know it's been a long time from "today" but my camera needed some "troubleshooting" and i hope i'm going to get the pics out tomorrow.
Sorry for the delay!:(

[dude8383]

I know it's been a long time from "today" but my camera needed some "troubleshooting" and i hope i'm going to get the pics out tomorrow.
Sorry for the delay!:(

its all good, just get the pics and we'll be cool ;)

[Zoso]

I have to ask - why? The E36 OBC is just slight better than the E30 OBC buy you really don't gain anything but a longer display and a funky looking install.

(As you can tell, I'm not a fan of modding just for the sake of modding :))

With that said, I'm looking forward to pics!

[Vladi]

Finally, the pics. The OBC install isn't in it's final form, i'm waiting to get my engine in and then i'm going to make a nice frame for it. Also since the pics have been taken i fixed the display as well. :D

[Vladi]

I have to ask - why? The E36 OBC is just slight better than the E30 OBC buy you really don't gain anything but a longer display and a funky looking install.

(As you can tell, I'm not a fan of modding just for the sake of modding :))

With that said, I'm looking forward to pics!

You answered yourself. :) The E36 OBC IS better than the E30 one. It's got lots of more functions than the E30 one. I've got both, so i know. :D I've retrofitted a CheckControl, too. I haven't made it 100% functional (rather like 60% of it works) because i don't have all the sensors from the 6cyl (like the oil one, for ex.) + it's cool, when i get in my car it looks like a spaceship with all the buttons. Ha!

[Febi Guibo]

love it!!!

(don't know why, exactly, but I love it and salute you!!)

how deep is the E36 OBC unit? is it DIN sized?

[Zoso]

It's not deep at all. I had mine (my E36's) out at one time. It's about as deep as it is tall - maybe a little deeper than tall.

[Vladi]

I'll take a pic tomorrow and write the dimensions. ;)

[silverblades181]

Did anyone keep the information on the swap? The link no longer works and I need to swap my 13 button into my other 318is. Thanks

[318isle]

Did anyone keep the information on the swap? The link no longer works and I need to swap my 13 button into my other 318is. Thanks
Funny thing is, I'm looking to do the same thing! I just scored an OBC from a friend and now I have no directions. :(

[Tonyb]

:( Funny thing is, I'm looking to do the same thing! I just scored an OBC from a friend and now I have no directions. :(

Same here! What happend to the link?

[318iSdaniel]

:(

Same here! What happend to the link?

heh, me too.