Time to post a wiring chart

[StreuB1]

Those in the know, that a look and let me know if you see any errors that jump out at you.

Engine is an M50TU from a 93' 525it, car is a 90' 325i, harness is from a 95' 325is auto. Swapped in S50 cams a few weeks ago, resealed and freshened the whole motor and threw on a set of OBX headers.

Converted the harness from auto to manual and the wiring is all done. Just waiting to get some feedback before I click the new C101 connector together and lock the pins in place. :)

[lifeiskaos]

thank you

[blazing]

"the only wire that needs to be modified is a “brown/black wire pin 26 transmission ECU” need to be connected to any “red/white wire on the main relay”. ECU has to be out of a 93-94 325I with the Bosch part number ending in 413."
This was taken from the site mentioned on the chart above.
Can anyone verify this needs to be done with an harness from an auto car.
I had not heard this was necessary.

[SamE30e]

"the only wire that needs to be modified is a “brown/black wire pin 26 transmission ECU” need to be connected to any “red/white wire on the main relay”. ECU has to be out of a 93-94 325I with the Bosch part number ending in 413."
This was taken from the site mentioned on the chart above.
Can anyone verify this needs to be done with an harness from an auto car.
I had not heard this was necessary.

That's if you're keeping the tranny ecu in and putting it in a 5spd car. It's for the neutral lock out I think. It's so the starter won't turn when the car is in gear.

If you cut out your tranny harness, this shouldn't be a problem.

[Mako18]

Looks good here is mine. 89 325is with 94 325i m40b25tu engine using a 95 525 harness.

[blazing]

Thanks for the clarification my harness has been pruned so I won't worry about it.

That's if you're keeping the tranny ecu in and putting it in a 5spd car. It's for the neutral lock out I think. It's so the starter won't turn when the car is in gear.

If you cut out your tranny harness, this shouldn't be a problem.

[StreuB1]

Hey guys thanks for the replies! Trying to stir up a little comradery on here. Seems like the wiring on these things is a black art persay. Be nice to gather up all the pin cross reference charts of known 100% working builds.

So I will have to look into this trans wire mod further at work tomorrow.

[StreuB1]

bump

no one has any input? lol

all the chart threads have some type of feedback. can i assume that means its good to go? lol

[etxxz]

4-12 won't work. (diff sensor)
not sure 11 to 19 prob wron't work either. (diff everything)
i'd be careful with 6 to 22 (heater relay to diag 12v source/req or diagnostics port)
20, you want ABS or no?
just red flags i didnt look at the diagrams for your cars. you should recheck.

[FredK]

4-12 won't work. (diff sensor)
not sure 11 to 19 prob wron't work either. (diff everything)
i'd be careful with 6 to 22 (heater relay to diag 12v source/req or diagnostics port)
20, you want ABS or no?
just red flags i didnt look at the diagrams for your cars. you should recheck.

Please be more constructive rather than offering up vague answers.

C101p4 - x20p12 is required. I don't know why you're saying it isn't. The sensor is different, but that's why you swap to an E30 cluster temp sensor.

C101p6 - x20p22 is required to power the diagnostic connector. Pin 6 is a hot in run and start power supply, which would be appropriate for powering pin 22 on the E36 engine harness.

Pin 20, StreuB1 noted at the bottom of his diagram that he powered pin 20 from the E36 main relay.

[etxxz]

hey, that is what jumped at me. i'm not going to do the work for him download etm's etc.. i already did that for a different swap crowd. i was simply pointing where to direct some attention.

[bad_azz_bmr]

hey, that is what jumped at me. i'm not going to do the work for him download etm's etc.. i already did that for a different swap crowd. i was simply pointing where to direct some attention.

I was wondering where can I download the etms from? I have an 88 and it looks like all the charts are off a little from each other ESP the wire colors.
Thanks

[etxxz]

ygpm

[StreuB1]

4-12 won't work. (diff sensor)
not sure 11 to 19 prob wron't work either. (diff everything)
i'd be careful with 6 to 22 (heater relay to diag 12v source/req or diagnostics port)
20, you want ABS or no?
just red flags i didnt look at the diagrams for your cars. you should recheck.

4-12 does work....its actually why it works. E30 use a single pin (sensor body sinks ground from engine) and E36 source ground from the DME. E30's temp gauge needs the proper scaling of the E30 sensor so this needs to be swapped. In order for that to work with the E36 harness, one wire is omitted since the E30 again is a ground sinking sensor. So yes, it does work and its the only way it will work. E30's temp gauges dance because they sink to ground and why E36's dont....they source a stable ground (DME).

11-19 also works. Pin11 on C101 is the service interval indicator reset trigger. When the diagnostic connector is given a reset signal from a peak tool it resets the service interval bar graph via Pin 11 thru C101. On the E36 harness that trigger from diagnostic connector X6002 pin 7 travels through X20 pin 19 to the indicator on the dash (connector A2 on cluster). So yes, pins 11 to 19 work if you want your service bar graph to read and not be dead or unresetable more so.

6-22 works because E30's have a seperate O2 sensor relay in regards to the engine harness. It gets its power from C101. E36 on the other hand have the O2 sensor heater relay integral to the harness and derives its power directly from the hot tap. So this normally would be just capped....but the diagnostic connector also needs power. Peak tools arent battery operated, they need an external power supply. They get this from X6002 pin 16 which travels through X20 Pin 22...which is now connected to the 12v switched hot from the chassis side C101 Pin 6 which used to supply power to the O2 sensor relay on the body...which isnt there anymore.


ABS power is noted




Thanks Fred, BTW. ;)

[StreuB1]

Oh and BTW. Pin 16 on C101 connected to pin 17 X20 is actually pointless on E30's unless you have an airbag car. The wires are there on the late model non-SRS cars but its dead after C101 on the body side. This is the SRS system diagnostic transmit line (from SRS connector X240) to the diagnostic port. Since a 1990 doesnt have ANY body electronics, there is no information for that pin to transmit so it can be omitted. Its an easy connection to make though and its good practice just in case. It wont hurt anything. If you HAVE a 1991 SRS car then you must have this connected.