Wiring diagram required for MK3 internal central locking switch

[JPW]

No way to get this done without taking the full door off, even at a squeeze? How do you access the inside hole that passes through the rubber tubing to the door?

[Nathan Buffery]

I'll study the wiring diagrams tonight. There is surely wires in place that go from the door to the BCM that are not in use and therefore could be used. My Focus doesn't have the door module so all the wires must go back to the BCM, so I'm thinking if you do have a module then maybe there are some spare wires that go through the door. Seems a bit extreme to have to take the doors off. 

[JPW]

Bear in mind I have the full four door power windows, power folding mirrors, heated mirrors and mirror puddle lamps, so possibly all taken. What I am interested in is what wires 11 and 22 in the door module harness are present for, as the harness says they are not used, so maybe these do nothing and go back to the bcm but not used.

[JPW]

Just found some descriptive text here - see attached.

Specifically:

--------------------------------------------

Power Door Locks

The BCM controls the door locks by sending messages over the Medium Speed Controller Area Network (MS-CAN) to the DDM and the PDM . The DDM and the PDM each relay the messages over a dedicated LIN to the Driver Rear Door Module (DRDM) and the Passenger Rear Door Module (PRDM) respectively. Each door module supplies power and ground to its corresponding door lock actuator (integrated into the door latch). The modules reverse the polarity to switch between the lock and unlock functions.

The BCM sends voltage signals to the door lock control switch. When the door lock control switch is pressed, the voltage signal is routed to ground, indicating a request to lock/unlock the doors.

Each door module also monitors the door lock/unlock status by sending a voltage signal to its corresponding lock/unlock feedback switch inside each door latch. The switch is closed when the door is unlocked and open when locked. The rear door modules send the information to the corresponding front door modules. The front door modules then transmit the door lock/unlock status to the BCM. The BCM uses the input from the lock/unlock feedback to determine if the indicator should be illuminated or off. The BCM controls the voltage to the door lock indicator.

If all 4 doors are locked and the lilftgate/luggage compartment lid is closed, the indicator is illuminated. If any door is unlocked or the lilftgate/luggage compartment lid is open, the indicator is off.

The doors can also be centrally locked or unlocked using a key in the driver door lock cylinder. When a key is used in the driver door lock cylinder to lock or unlock the driver door, the DDM detects the lock/unlock feedback input change state and sends a message to the BCM indicating the lock/unlock status of the driver door. The BCM correspondingly sends a command over the network to the DDM and the PDM to lock or unlock all the doors.

In the event of a failure of the power door locks, the doors can be individually locked through the manual door lock. The manual door lock is located on the rear edge of the door just above the door latch opening. For the doors on the left side of the vehicle, insert a key and turn clockwise to lock. For the doors on the right side of the vehicle, insert a key and turn counterclockwise to lock.

Based upon input from the door lock control switches, the lock/unlock feedback input, the keyless entry keypad, the passive entry system and the RKE transmitter, the BCM unlocks the driver door, unlocks all the doors or locks all the doors.

Door Lock Control Switch

The door lock control switch is a momentary contact switch that receives voltage from the BCM on the input circuit. When the switch is pressed, it routes the input circuit to ground, signaling the BCM to lock or unlock the doors. When the switch is pressed, the doors lock or unlock depending upon their current state.

The door lock control switch contains a door lock indicator that is used to indicate the door lock status.

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Bsed off the following excerpt would you say that I might be able to tap in to the "lock/unlock feedback switch" in the drivers door ad wire it to the door lock switch?

The doors can also be centrally locked or unlocked using a key in the driver door lock cylinder. When a key is used in the driver door lock cylinder to lock or unlock the driver door, the DDM detects the lock/unlock feedback input change state and sends a message to the BCM indicating the lock/unlock status of the driver door. The BCM correspondingly sends a command over the network to the DDM and the PDM to lock or unlock all the doors.

There is a wire (circuit CPL30) on Door Module Connector A pin 19). If I wire that to the button then a press should switch the voltage to ground and do as per above?

Maybe...

James

System Diagram Locks.pdf

[Nathan Buffery]

8 hours ago, JPW said:

Bear in mind I have the full four door power windows, power folding mirrors, heated mirrors and mirror puddle lamps, so possibly all taken.

But you have a door module, so I was thinking that, instead of lots of wires going back and forth to the BCM, you have 2 Cambus wires. Therefore, if (a big if I know) the loom is the same, there would be spare/unused wires you could use. 

[JPW]

Good idea. Here the wires I do have going to the module.  Of course some of the are coming in from the BCM and some will be going out to the window switch, mirror, handles etc, so need to work out which are from BCM and then if any are free.

 

[JPW]

Hi @Nathan Buffery

Did your wiring diagram research yield anything?

Cheers

James

[Nathan Buffery]

I'm slowly working my way through it, as it's not so easy looking at the PDF on my phone!!! 

I'm trying to concentrate on connector C25 which I think is the Drivers Door (RHD) and identify each terminal. One possible set of wires is the keyless locking system that I think use 6,7,8 and 12 on the "A" connection. 

However, I'm starting to have doubts if the car is not fitted with keyless locking, they might use these terminals for some other function. 

[JPW]

See attached PDF - for Connector A. 6 and 7 don't exist (wires are not there either), 8 is CTRL MOD - REAR DOOR DRIVER SIDE LIN BUS and 12 is CTRL MOD - WINDOW MOTOR DRIVER # DOWN

CVC501A.pdf

 

[Nathan Buffery]

No I was talking about the connection that goes from the door to the car. I think it's c25 as below.

As you can see the top half is connection A and the bottom is B. 

[JPW]

Ah, I see. Where is the other end of this? Does it go to the driver footwell, centre console area or BCM? Just thinking where to tap in to the wires so need on the inside of car...

[Nathan Buffery]

Yeah I'm not sure where the keyless module would be situated in the car. @JW1982 do you know? Be nice if it was in the passenger footwell!!! It says on the diagram that the wires go from the keyless module to the "Front Door Handle Switch Unlock". I'm not sure if this is the interior or exterior handle. If I have the right connection (think it's C25, but I'm not sure if the diagram is explaining a LHD when talking about the Drivers Door) you would be looking for wires A8 = yellow, A6 = green/Brown, A7 = yellow/violet & A12 = blue green. Presumably, these wires would be unused or in a tapped up connection.  

[JPW]

Here's the wiring layout for that harness (albeit LHD). Looks like it goes from the door to a number of places inside the car, from Connector C25 A/B as you say

 

The keyless module is right rear near the boot by the looks of it. (top right of image). Again, confusing a the diagram is for LHD so not sure if its all reversed in a RHD? If so it looks like the wires from the door (for keyless unlock) go past the BCM then down the left of vehicle to the rear left keyless module.

I'm not fussed about running the two wires I need from the BCM as long as I can splice in to some unused wires that go to the door. Even if it's near the driver door side. Just need to know where the wires go inside of car.

 

[Nathan Buffery]

So you will need to try and track down this door handle switch connection and see if the wires are in there and are not in use. 

It took me ages to find the keyless module connection on the diagram (labelled KVM). There are 5 of them; A,B,C,D & E (page 102). I'm not sure if all of them will be in your car or even which side, but I would imagine they will be behind the boot trim. I remember on my focus, which is an estate, there were lots of connections tapped up on the passenger side. If you can locate connection A, then terminal 3 and 15 would be the wires you are looking for. 

Personally, I think I'd be tempted to try a facelift module before going down this route. 

 

[JPW]

Cool, will check if the wires exist in the door first. I was hoping to tap in to these spare wires somewhere around the driver/passenger area, which I presume these wires do pass to get down to the rear of the car where the keyless module would live... I might put a tone down the wire from the door harness if it exists and trace it in the car.

[Nathan Buffery]

To be honest I'm surprised there isn't a inline connection, but I can't see one on the diagram. If your lucky the wires will pass around behind your glove box. I wonder if @Tommo17 might have a better idea as i think he said he has a spare wiring harness.

[JPW]

Regarding just trying the facelift door module, I think there is more to it than just this. Looking at the diagram below, the facelift door module wires (11 and 22) seem to go to a "memory" module which then handles the illumination, lock status led and lock/unlock. And this goes back to the BCM, C2280B-36 (C2-36) and C2280C-36 (C3-26) and which, on the pre-facelift, doesn't have anything there (it's blank).

 

[Nathan Buffery]

I still have a nagging feeling that the terminals on the door module 4, 14, 15 and 17 could be used, but I think something in the door module would have to be changed in Forscan. There is a Power Lock Enable. Address 726-37-02. Maybe I'll ask on the forscan forum.

[JPW]

Not sure it will do much on a focus though, looks to be an F150 rear tailgate release thing...

[JPW]

I am home tomorrow so going to spend some time tracing wires from door to car and figure it out...

[Nathan Buffery]

I was under the impression that the F150 spreadsheet was what everyone uses for the focus mk3 and 3.5.

[JPW]

After another look and tracng wires from the door to inside of car I'm afraid it doesn't seem posisble without drilling a hole in the the C25 connector. to add extra wires. The harness going to the door in my car doesn't include the keyless wiring so there are no spare wires I can reuse.

I am probably either going to try and mount the facelift door lock switch somewhere in the centre console or just purchase one of those push button with led from eBay/Amazon and wire to that.

I wired the facelift door lock switch temporarily to wires 2 (door lock status led) and 6 (lock/unlock signal) of the original FCIM harness and the button and lock status led do work.

[Nathan Buffery]

That's a shame mate. I have posted a question on the forscan forum about the module, but no takers yet. 

You'll find the facelift switch would have to sit about 10mm below the panel so it sits flush. I've ordered a switch from Ali express, but I was unable to find one with a backlight. I'm looking at mounting it on next to the hazard warning switch if there's room behind. I will also be fitting a Heater Rear Screen button the other side because I have used the facelift centre console (I'll post a guide when I've installed the switches). 

Did you check if the terminals, for the keyless locking, were free? Or are they being used for something else? 

@Monks600 did you have any success with this? 

[JPW]

You mean the terminals in the C25 connector just before the hole out to the door?

Unfortunately I couldn't locate/see it behind the drivers dash (I didn't remove anything, just took a look through the coin holder you remove to get to the ODB port). I think you'd need to strip a bit back to locate it or indeed take the door off and pull it through that way. Even so I would need to remove it and it seems like a pain in the..

If I decide to go for an aftermarket swich, I am going for this https://www.amazon.co.uk/Momentary-Button-Switch-Light-Latching/dp/B07XY53HF9 or this https://www.amazon.co.uk/Mounting-Momentary-Button-Switch-Waterproof/dp/B07G6ZCLGV/ - cheap and have an LED ring, that I plan to use for the door lock indicator, i.e. use the wire from FCIM 2, which sends the 12v signal only when the door is locked, and thus when locked the LED ring should illuminate, and be off when doors unlocked.

[Nathan Buffery]

Yeah I was talking about that c25 connection. 

I think you'll need the non latching switch. If it latches it'll make the connection and I think you'll find it'll cycle through locking and unlocking, as it's a one button. The ones I've ordered are custom so it will have a picture of a lock on the button that will light up (via the led terminal) when locked. As I said though, I couldn't find one that has a backlight so it won't show up in the dark. They are coming from China 20-40 days!!!