No ground to main or fuel relay???

[omar85]

I put an M20b25 in my '91 318i. I am not getting fuel or spark. I am not getting ground to the terminal 85 on the fuel relay or the main relay. I can manually get the relay to click and manually get the fuel to come out.

I am not sure if the ground is a switch ground. I ran the tests from the Bentley manual on the motronic plug. All the tests checked out perfectly besides one. The test for "Terminal 50 off the starter" is supposed to be power when ignition is on (this is plug 27 on the plug). That is the only test that didn't work.

I hope these are related because then maybe i can get my car running. Any help would be appreciated.

[omar85]

update: some more info...

pin 86 has continuity to one of the 2 pin 87's on the main relay.
pin 30 is always power
pin 87 has continuity to fuse 11

i think my problem with both the main and the fuel pump relay is pin 85. it receives no signal on either relay when i turn the key on. where does it get its signal from. does it have to do with the terminal 50 on the starter??? thats the only test that failed on the ecu diagnosis.

[FredK]

Omar, which pin did you test for Starter Terminal 50? Did you test for voltage using the diagnostic connector?

EDIT: I posted in your thread on bimmerforums.

http://forums.bimmerforums.com/forum/showthread.php?t=1055243

The problem I bet lies in the unloader relays. They aren't getting signal unless you hook up C101 pin 15 to Starter Terminal 50.

[omar85]

wow i gave up on that thread i didn't know it had all that info in it. i connected the pin 15 to the terminal 50 on the starter but no luck. the blower motor and windows work now. do i have to connect the 3 prong connector in the glove box to get the car started?

any more suggestions.

[rs4pro3]

the relay grounds are switched by the ecu itself, and yes that 3-pin white plug under the dash has to be connected, what year is the 325i engine and harness?

[FredK]

In the Bimmerforums thread, he said it was a 1987 M20B25.

[rs4pro3]

http://www.e30tech.com/forum/showthread.php?t=62885&page=2

take a look at that thread, there are some wiring differences between the c101 plugs, depending on the year

[omar85]

the relay grounds are switched by the ecu itself, and yes that 3-pin white plug under the dash has to be connected, what year is the 325i engine and harness?

i connected the green wire (middle wire on the c104 3 prong connector) to switch 12v power. now my main relay switches on. my motor is an 87 into a 91 body. i didnt connect the white wire anywhere. what do i connect it to?

[rs4pro3]

White wire is the fuel rate output from the ecu, that goes to the OBC and fuel econ gauge in the cluster, this should run to pin #8 on the c101 plug
This pin is probably empty on the engine harness side of the 87 harness, but should be present on the 91 harness.

[omar85]

is that necessary to turn the car on. i still don't have spark. any ideas.

[omar85]

edit: fixed/