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Discussion Starter #1
Guys I have an E46 coupe, i have a fault on the central locking, I am going to send off the GM5 for repair later this week.

On my coupe there is no key access on the door handle the lock needs the central locking to open the actuator, as the 'open' relay is damaged I cant open the passenger door

I have a wiring diagram that shows two acuator motors and three wires connecting them which I pulled from Haynes

As follows
Lock
Unlock
Arrest

The door is currently arrested and I need to get it open, can i apply a voltage to fool the acuators into opening and allow me to get my MOT as its failed on this
 

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Discussion Starter #3
yes i will snip the wires just before the door lock and apply a voltage to correct wire to pop it open, just need to be sure im ok doing that
 

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You might like to try giving the GM5 module a firm tap. Bang it against your hand. It can give enough of a shock to make the module work well enough to operate door locks one or twice. I often do this to open a passenger door so I can comfortably refit the module after repair.

Your idea is sound enough. Take the two wires that are across the arrest motor and get the polarity right so it unlocks. Again it might be easier to cut the wires near the connection to the GM5 module, rather than try to take off the door card etc. (unless you have already done this.

Do you know for certain if the GM5 is faulty? I assume the other doors do not unlock from inside and fuel filler is also faulty.
 

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Im not one hundred percent sure its faulty, but all door close on remote fob and none will open, I have three wires connecting the two 12v acuator motors, Black, White and Blue, does anyone know how to apply the voltage to pop the locks open?
 

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Discussion Starter #7
The door mechanism and acuators is brand new so not likely to be faulty, ive been getting in and out using the key in the drivers door.
 

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doing the key in the drivers door should unlock all the doors ...

You need a 12v source, so your battery would be a good one,

if you looked at the schematic i linked for you, you would be able to see that you do have three wires for the two actuators and that both actuators are wired in series, so you have two (of your three) wires one at each end and the third wire to mid point of the actuators, ON the schematic they are lablled: MZS MER MVR. You can see that they are connected to the same point (30) in the GMU so it dosent matter what way round you power them,
start with:
MZS to MER
MVR to MER

you should be able to opperate each actuator individually
 

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The fault the OP has described is caused by the GM5. I will put money on it.

I would really try tapping(firmly) the GM5 module while you operate the locking system. It works all the time as a last ditch attempt to open the door before I replace the relays.
 
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