color coded pinout needed for auto TPS

[nebraska_e28]

I am getting ready to wire up an 89 535i TPS from an automatic for custom use in an e28. Unfortunately I have the switch but have been unable to source a plug w/wires. Unless someone has a plug they would sell, I'll be making my own harness. Could someone provide me with a pinout that actually tells what pins on the switch correspond with what color wires on the harness? I was able to find this picture on the forums & I know what each of the pins is numbered, so the only problem is knowing what color wire for what pin. Thanks in advance!

Cheers!

http://www.bimmernut.com/%7Ebillr/images/tps%20adjust.jpg

[Ross]

Dealer ought to have the plug and short leads with the crimped on connector.
Terminals are identified on the switch
2= normally closed idle signal brn/blue wire in harness
18= ground (common terminal) brn/orange wire in harness
3= normally open WOT signal brn/blk wire in harness

The colors are from E34 but I'm confident same on E28

[nebraska_e28]

Dealer ought to have the plug and short leads with the crimped on connector.
Terminals are identified on the switch
2= normally closed idle signal brn/blue wire in harness
18= ground (common terminal) brn/orange wire in harness
3= normally open WOT signal brn/blk wire in harness

The colors are from E34 but I'm confident same on E28


I forgot to mention this is a 6-pin TPS, not the 3pin found on manuals. I'm pretty sure it came off a 89-90ish 535i that had EH automatic transmission. I was able to source just the connector (w/o pins) & rubber boot from the dealer.

[Ross]

Never heard of it. I assure you though that 89-90ish cars have a three wire TPS. So do the old L-jetronic cars.
Sorry I can't help.

[nebraska_e28]

Never heard of it. I assure you though that 89-90ish cars have a three wire TPS. So do the old L-jetronic cars.
Sorry I can't help.


Perhaps I'm in error & referencing the wrong year? The picture shown is the exact TPS I have & need to wire up. What years did this come out of? With that info, would you be able to provide the info I need? Thanks again!

[Ross]

I'm not familiar with this as shown in the diagram.
Your E28 will only be concerned with two things: throttle closed? throttle wide open. Terminals 4,5&6 will provide that.
The scematic indicates the other three terminals would offer a variable resistance predicated on throttle opening, not useful for the E28.
Where is the diagram from??

[Ross]

I suspect this is Mono-jetronic, '70s vintage?
Someone check me please regarding the E28's ECU needing only idle/WOT signal.

[nebraska_e28]

I'm not familiar with this as shown in the diagram.
Your E28 will only be concerned with two things: throttle closed? throttle wide open. Terminals 4,5&6 will provide that.
The scematic indicates the other three terminals would offer a variable resistance predicated on throttle opening, not useful for the E28.
Where is the diagram from??

Someone had posted that diagram from a shop manual on this site. I did a little more research & found that the TPS that I'm using came in a 89-93 535I M30 w/automatic EH transmission. It is a variable resistance TPS only used on the autos. Would you or anyone else have a lead on where I might find a wiring harness for it? Here's a pic. Thanks

http://members.cox.net/nebraska_e28/E34_Auto_TPS.jpg

[Ross]

Nope, sorry no harness. Why not just use the 3 wire TPS, it ought to plug right in. New part, no fuss connecting it. ?

[nebraska_e28]

I've been unable to find an original used replacement, & a new is retails for $200+ . A plus of using the one from E34 is that it is much more compact than the huge TPS & separate WOT switch they used on the E28. I was able to find a color coded pinout, now hopefully I'll get lucky on the board & find a harness.

Thanks again!

[Ross]

Bosch # 0280120321 3 wire TPS for '89 535i manual $47.30 @ autohausaz
" 0280120406 6 " auto 121.07 "

[nebraska_e28]

Thanks a mill Ross! I appreciate it, not to mention this site will come in very handy for other needs also with these prices.

LJ