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Rear doors won't unlock since battery went flat, also "Child Lock Malfunction"

Started by bengo, September 08, 2017, 12:33:06 PM

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Hi there, first time poster, nice forum.

Our battery went flat (lights left on). The breakdown person restarted it. Now we have various problems:

- there is a fault message on the screen "Child Lock Malfunction"
- the rear doors are locked and stuck locked and shut: they won't unlock when the keyfob is used, the locking lever is in the locked position and when you move it it's springy but nothing unlocks.
- you can't open the doors from the inside or outside, i can't get my toddlers into the car and we need to move!
- the rear windows aren't responsive when you operate the controls

Less crucial, but possibly helpful in diagnosing:
- the hazard lights no longer flash when you lock the car with two clicks on the keyfob.
- boot is operating fine
- front doors operating fine

I've ordered an ELM device and bought Forscan but it won't arrive until tomorrow. No Ford dealership within 20 miles can fit us in until next week and none could give advice on phone.

Is there anything I can do at all to get the doors opening and closing? It feels like something has gone wrong in the computer since the car was started by the breakdown person and there should be a simple hard reset but I've never got nerdy with my car so I don't know the basics I'm afraid. Keen to learn as I can't go anywhere without the car and we've big trips coming on Saturday and Monday!

(A smaller issue: the radio is asking for a code, I held down 1 and 6 together to get the serial and then buy the code online, but contrary to all online advice it never shows a serial number beginning with an M or a V? It seems to me that if you can buy a "security code" on the internet for a few pounds then that's not a "security code" it's a "massive waste of everyone's time").

Apologies, this is a Ford Galaxy 2011.

Also, I've already tried this reset procedure (holding down child lock button for 1 second twice):


I've also tried a suggested central locking reset procedure (turn ignition on and off four times quickly, wait for beep, then press lock/unlock on fob, wait for beep, open and close door).

Neither of these things worked.

I understand that this is an old post but I've recently had this problem and found the solution so thought I'd share.
It's a bit lengthy and involves some minor disassembly and electrical knowledge so is best given to a vehicle technician or similar person. All in I was done in about an hour and a half including tea break so it's not too bad.
After a flat battery on my 12 plate Ford Galaxy mk3 I had a 'child lock malfunction' message on the dash, and both rear doors were completely unresponsive electrically on windows and door locks - from the keyfob, drivers door switches, and rear door switches. I could open the drivers rear door and lock/unlock it manually from the interior lock handle but the passengers side rear was stuck in a locked state and the interior lock handle was stuck and felt 'springy'.
I tried the posted solution of resetting the locks by pressing the child lock button for 1 second twice without luck.
After checking rear fuses RA3 and RA4 for voltage at both sides I figured that the problem was the child lock function, as this disables both rear interior door handles and also the rear windows.
The problem arises when the vehicle is locked with the deadlocks activated (interior handles disabled) and the battery goes almost completely flat. When the vehicle is unlocked via the keyfob the deadlocks attempt to de-activate, but low battery voltage causes one to release and the other not, or one /both to end up in some intermediate position.
This causes the rear door modules to report implausible states to the vehicle, causing the 'child lock malfunction' message and the vehicle to play safe and assume child locks are 'ON'. The central locking motors are also disabled due to unknown deadlock positions.
The solution is to force the deadlock motors into their off position electrically on both rear doors.
I partially removed the rear door interior panels at the top end, and disconnected the big multiplug from the door modules. This can be done even with the door(s) stuck in their closed state.
There are apparently 2 flavours of rear doors on this model - one without rear door modules and one with.
If you have a missing fuse RA5 and you have both fuses RA3 and RA4 then you have rear door modules. This is what I have on my vehicle so this solution is for that variant.
The attachments aren't too clear but from the wiring diagrams for both rear door modules I can see that the pinouts are the same. Pin 7 is 'LOCK COMMON' and pin 9 is 'DOUBLE LOCK'. To force the deadlocks into their 'OFF' position, I applied battery voltage to pin 7 'LOCK COMMON' and ground to pin 9 'DOUBLE LOCK'. This reverses the deadlock motor to its dis-engaged position. As this is done the lock motor is heard to move. I repeated this on the other rear door,  reconnected both door module multiplugs and cycled the ignition.
The door locks and windows all came back online and the fault message disappeared.
It should be said that sticking battery voltage where it doesn't belong can cause component damage and you should only do it when you are sure you have the right pins. The voltage source should be fused at a suitable value. I used a power probe which includes an 8 AMP safety fuse. Also use suitable probes to avoid spread pins. In my case and working from home with limited tools I chose to back probe the module connector with small pins to avoid connector damage.
Anyway, hope this helps. I rarely post solutions as it's pretty time consuming but I'm on Xmas break so figured I'd post this and support the forum. Cheers.

Good work there, thanks for the details it should help others in future