First, before any other work is done
Use an obdII scan tool, or you can just remove the ecm fuse or disconnect the battery.
unplug the 12v batt for at least 30's
Disconnect the battery and remove the glove box, lower finish panel and ECM. Disconnect the blower motor wire harness and the three mounting screws.. Remove the blower motor.....
Disconnect the battry for one hour: then reconnect-That should do it.
(1) disconect battery ( 2) under hood on passenger side remove 2 10mm boltes (3) pull ecm out disconnect 4 wire pluges
If its anything like a 325e you will find it in the glove box. Open the glove box look for two BLACK screws remove them, reach back and remove two fixing plastic bolts by twisting them 90 degrees, remove the plastic cover and the ECM should be there held in with 4 10mm bolts. Disconnect the battery before unplugging the ECM
The ECM is located behind the glove box. Remove the glove box door. You'll see the ECM. Disconnect the battery. Remove the three plugs on the bottom of the ECM. There are 4 nuts that hold the ECM in. They are 10mm. Remove them and pull out the ECM. Install is just the reversal. Remember to take your PROM from the old ECM and put it in the new one. New ones don't come with the PROM and it's highly probable that a used one will have the wrong PROM installed as each one is programmed to each specific car.
Remove the glove box. Look under the dash. You should see the ECM inside a plastic enclosure, bolted to the firewall. Remove all bolts, unplug the ECM from the harness, and it will come right out. Install the new ECM in the reverse order to remove the old one.
unplug your ECM B fuse that should shut it off
The ECM is located under the dash behind the glove box. To remove the ECM. 1. Remove the glove box. There is a release under the box, push it up to release it. 2. The key should be off and preferably pull the battery cable before removing the ECM. Working thru the glove box opening: 3. Release the latches and remove the wire connectors. 4. The ECM is held in with bolts, remove them and the ECM will pull out. Reverse the procedure to reinstall the ECM.
Your ECM should be located on the passenger side of the car. remove the glove box and it should be on the outide wall. I am not sure that there is an acual fuse for this. but that is where the ECM is located. i hope that this is helpful.
Remove glove compartment. You will see two bundles of wires running up into the dash area. They both run to the ecm. Simply unplug the plugs from ecm and remove two 10mm bolts and the whole unit will come out. Don't forget to disconnect battery power before doing this.