Not the average door actuator issue

[Uberjava]

So… 2010 NC.

All of a sudden, the central locking on both doors doesn’t work at all.

1. The key fob is powered and the car receives its signal. If you lock both doors manually, you can switch on the alarm (flashing side lights). I can also pop the boot via the fob… so it’s not the fob.
2. It’s not the 20 amp fuse to the central locking/boot lid. Replaced, and the boot lid pops anyway.

Here’s the big problem. Whilst I can unlock the driver side with the key and I can use the internal drive side door lock switch to lock and unlock that side, the passenger side’s door lock switch does not unlock the door.

The cables running from the passenger side internal door release and lock switch are connected to the actuator and lock, and seem to be doing what they are suppose to do, except that the lock doesn’t disengage.

So since the passenger door is locked, and keeping itself locked, I cannot open the door.

Even if I remove the door cards enough to access the actuator, there’s nothing I can do to release it and as far as I’m aware, I can’t remove it without getting at the three screws with the door open.

I’m not even sure it’s an actuator problem though, that a lot of people get. If it was, the driver side should still respond to key fob signals?

Could this be an electrical issue? Could the control module for the central locking (wherever that is on an NC, I can’t seem to find any information on the location of it), have malfunctioned and dead locked the doors? The driver side key may well of overridden the dead lock on that side, but perhaps, even with the internal lock switch functional, the passenger side lock just stays locked? Does this sound reasonable?

Would it be possible to give 12v into one of the pins to the actuators to get them going?

I don’t want to give up on this and hand the car to the Mazda dealer near me, as I’m going to get fleeced!

[MickAP]

For the price of a fob battery I’d renew that first, if you’ve not already done so.
I know it sounds like it’s not that but my fob would open the boot but not the door locks on time, that’s if I stood close to the car.
A twiddle also on the prong contacts in the fob to make better contact with the battery is also worth trying whilst the fob is open, cheap fix anyways if it works.
So I take it neither door opens on the fob and definitely not the passenger side if you just use the key in the lock driver side?
I’ve changed door lock actuators before but never messed with anything do do with the control module for these.
How long have you owned the car and has anyone (if you know) done anything to the doors/locks or fitted say those bushing to the door jams at all?
Just trying to establish why that passenger door has jammed. My only thought maybe the security plate near the handle has worked free and jammed the cable operation, it happened to me but I forgot to tighten mine up when I removed it one time.
Only suggestions of course to look at but of course you need to get that door open.

[portvalenil]

It sounds more mechanical. Perhaps that is stopping the electrics kicking in for safety reasons
If I couldn’t find a mechanical issue and I’ve changed the battery and checked the fob I wouldn’t shirk going to the dealer.
In my experience with Ford and Hyundai they don’t have on site electricians but have first call on contractors who otherwise tell you there is a month wait if you ring them direct.

[Roadster_Robbie]

Yes, I does sound like the left door is stuck deadlocked. I can’t understand why the right door is not locking or unlocking from the transmitter though, but I revisit that concern once the lock fault is fixed. If you post your VIN I’ll let you know which wires to power up to see if you can get the dead lock off.

[Roadster_Robbie]

Thanks for the PM with your VIN.

I reckon that the easiest place to access the wiring is from the Keyless Control Module. This is located in the passenger foot well or behind the glovebox, I’m afraid that I can’t be more specific as to it’s exact location, the diagram may help (or not)…

You’re looking for a module with 3 plugs, a 6 pin one, a 30 pin one & a 27 pin one. There may be more, but you’re looking for the 6 pin one. It should have a Light Green, Black, Green/Black, Grey, White/Green & Blue/Red wires going to it. The Green/Black, Grey & Light Green wires are for the door actuators.

I think that if you disconnect that connector, apply 12 volts to the Green/Black wire and ground the Grey wire, the door should unlock. Only pulse the 12 volts for a short amount of time, no more than 1 second.

You also may want to check the connectors at the control module for corrosion while you’re in there.

Try the above at your own risk, but let me know how you get on with it…

Edit… Actually, have you got the door trim off? You could probably do the live and earth at the lock if it’s easier access. I think that the wires are the same colours but I’d need to double check.

[Uberjava]

I’ve had the trim on and off again, nicely removing some skin and nails…

I will have go in with some contact cleaner on the keyless module.

I was wonder what was the best tool to generate 12v to small clips to power the circuit? A full battery is a lot of amperage for a fiddly little set of clips.

I’m using the car at the mo… but I reckon I’ll have time to tackle this Wednesday or Thursday… Or maybe it’s RX8 fixing day on Wednesday…

[Mad_Malc]

@Uberjava

best tool to generate 12v to small clips to power the circuit

9 volt PP9 may just do it. (Used to rewind Volvo rear hand brake) or an alarm/motor cycle battery or a smart charger. (Use 6 volts first and see if it works)

[Roadster_Robbie]

I’d just use some lengths of wire with the ends bared and twisted pushed into the back of the connector and flash the live to the battery terminal and put the ground on a suitable place nearby.

[Uberjava]

This has all been very helpful. thank you very much!

I am hedging my bets it’s the keyless control module or loom that’s the issue. I think it’s nigh on impossible for both actuators to die simultaneously…

Looks like a 9 volt will fire off actuators … so I’ll probs try that first…

Regards

H

[Uberjava]

Right… update on this one…

Found the keyless control module, found the 6 pin that goes to the doors, removed it cleaned it with contact cleaner. It looked pretty good anyway though.

Downloaded the wiring diagram from Mazda. Understood what I had to do. Made a 5 volt 2-wire lead powered by a USB power bank.

Disconnected the battery. Took the trims off, applied power directly to the door actuators from the back of the connecters at the door itself. You can hear the actuator moving on both doors.

However, no luck getting the door to unlock.

Whilst fiddling with the drivers side door, I could get it to dead lock, override that with the key manually, but no combination of applying voltage to the actuator and hearing it move, could release the dead lock. Only manually with the key.

So although I couldn’t release the dead lock with applied voltage on the drivers door, I still tried with the passenger door. Got the actuator to move with positive and negative voltage applied, but alas, no dead lock release…

Next step, replace the awkwardly located keyless control unit, and see if that does anything.

[Keat63]

The locking mechanism has a small electric motor with a worm gear.
These are prone to failure, but like you rightly mention, unlikely for both to fail simultaneously.
However, if it turns out to be such, then I found a load of info on the motors themselves.

Drivers Central Locking NC - Actuator technical info

The central locking failed on the drivers door about 5 years ago, so I fitted a used actuator. Ive just been out and its blooming failed again. It makes no sense why its the drivers side, I mean the passenger side has operated just as many times.

[Uberjava]

I’m going to keep updating this thread, for my own sanity and also for anyone else who comes across it in the future.

So… symptoms, central locking not operating either side, left passenger door not releasing. Fob working, boot release working, alarm working when doors manually locked.

Update* … took it to my local Mazda dealer, who diagnosed the problem as the passenger door actuator. They removed the actuator that enabled the door to be opened. I didn’t want to suffer their prices, so I elected to fit my own actuator and I got one off eBay for £28.

Now… point one… it looked a lot like he forced the actuator off to release it, as it came back sheared off from the lock.

point two… I have the wiring diagram from Mazda and it has the wires from the control module running to both doors as being in parallel. So it makes sense that if one side fails, the other side should still work, and that seems to be the case for a lot of people on forums. I explained this to Mazda but didn’t have a reasonable answer.

point three… if you apply voltage to the old actuators (gave it 5 volts) you could hear them react.

So… I have another door lock/actuator. It’s second hand but for fun, I’m presuming it’s working.

I plugged the loom in, without actually fitting it in the door. Simulated the door being closed and… nothing… no dice… no change…

State of play* … At least my door is released (at a cost of £220 from Mazda) … I’m going to fit the replacement lock and actuator (as the old one has been sheered), and I’m reasonably confident I will be able to manually unlock and open that side.

Things to do further* … I am going to get a multimeter and test the resistance of the loom from the wireless module to the doors… and then test to see if I get any voltage from the control module when I lock/unlock the doors. If there is a lack of voltage, I’m going to go through the arduous process of swapping out the control module, as I have a spare.

It’s awful to access! With the white plastic under dash that surrounds the blower, in the way, then getting another board in will be a total pig to do!

I’m making the assumption that if the replacement module is in, then it doesn’t need tuning/being given codes, as it’s not the remote receiver module.

That’s as far as I’ve got…

[Uberjava]

Ok. Door lock replaced. I can lock the door manually, but nothing electronically.

I did some investigation to the NC door lock and I found something interesting that explains what went wrong with my door in the first place.

The white plastic arm from the actuator docks with the white plastic square receiver in the door lock.

When the door lock receiver is in the ‘down’ position, the door is locked.

Opening the door with the door handle, moves the switch into the down position. Only by having the door actuator arm present stops the lever going from ‘up’ to ‘down’.

So, if your actuator arm is not aligned, opening the passenger door will permanently leave the lock in the ‘down’ position and the next time you close your passenger door, the door remains locked.

This is what happened to mine it seems, and the only way I know to remedy this is to apply critical force to the actuator to snap it off the door lock, then move the square white lever back to the up position!

Or succinctly put… If your actuator arm isn’t in the right place, using the door handle will permanently lock your door the next time you close it and there’s nothing you can do about it but smash the actuator off the lock and push the switch back up again.

Why my central locking system refuses to come back to life though… I think I’ll let an auto electrician figure out!