[tracer bullet]

Did you test all the wires from the ECU to the actuator and ensure that 12V or something similar was headed to the actuator? That was the step to do and be sure if it was the ECU itself.

Paging 3 Series owners with multimeters and a few minutes to spare...

[mageeda]

i did try to test the wires but someone mentioned that i would not get proper voltage if it it is not grounded is that right,,??? there are 4 wires on the plug that goes into the actuator.. the only thing i get is one wire with constant power around 6volts ( when not grounded and unplugged from actuator )... anyone that can check the power going to actuator would really help....
thanks..

[mageeda]

anyone know how i can check to see if power is going through the trunk actuator wires when button is pressed? or if its live 6v constant....?? or should it be more.?

[mageeda]

yo tracer .. any help here??

[tracer bullet]

A multimeter probing a wire with one lead, and the other lead attached to some solid metal on the car which is actually grounded to the battery (or just go to the negative terminal on the battery itself if it's handy, will work to measure voltage.

You are off to a good start it seems with one wire having voltage. I can't tell you what you should have, if 6V is right or if it should be something else. Nor if the other wires should have anything in them, or when. You'll need 2 people perhaps, one to probe wires while the other tries to unlock the trunk.

You will also need a wiring diagram to compare to, to tell what the wires are for, and what to expect. I would guess that the ECU will send something to the actuator, perhaps 12V or so, 12.6 with a healthy battery. And that it will do so for a couple of seconds when you tell it to unlock the trunk by pressing a button. With a fuse somewhere along the way that can also be checked. But I really don't know your car, or have your car, or a wiring diagram for it.

[mageeda]

yes..i have checked all fuses, i have followed the wire from actuator to ecu and it is a very solid wire with no breaks... i cant really test rear ecu as there are big plugs coming from it and i would not know which wires on plug are the hot spark wire to actuator.... just wodering if it could be anything else other then ecu?? all other electric stuff in rear of car works..