Topic

The central locks of my TF will unlock with the keyfob, but won't lock. Keyfob has new battery, also the alarm is set when I press the lock button. Also locking with the door key only locks the drivers door, not the passenger door, and also the alarm is set.
2 years ago I have replaced the pektron relay for central locking, I would guess this is still not worn out, so that leaves the door lock mechanism itself.
Before disassembly I would like to test it on the vehicle, and to to that I need the color wiring for the lock motor. There is a 6 pin connector, and probably 3 of these are for the motor. The car wiring loom side has different colors from the lock-loom side. I have made pic's of the situation.
Anyone already done such a repair, and knows how to test the lock mechanism on the car ?

Thanks for helping

Your description of the problem point me exactly to the conclusion that relay in SCU unit is not operating on one side (one side of relay controls central locking, other side controls central unlocking), nevertheless it was replaced 2 years ago.
So from my point of view you need to replace that relay in SCU.

I assume that your pictures represent male and female side of the same connector. Male side of the connector has wires that go to door locking actuator.
On the female side of that connector (wires go into the car loom) you have (visible on pictures as well) orange and pink wire (thicker wires) on pins 3 and 6 respectively.

These two wires operate door unlock (orange)/lock(pink) respectively. When you put 12 V one one wire, other wire must be grounded.

WERY IMPORTANT INFORMATION: DO NOT apply constant 12 V on these wires because you WILL fry the motors. What you need to apply is just a pulse of 12V.

Hi there,
most problems are caused by the superlocking relay in the SCU -but if you do replace this relay it is best to replace the central lock relay at the same time.
You probably know that the original relays in the SCU were short lived items and much better relays are available .
I do have the colour codes for the eclectic locking on both sides and away of testing out of the car..
There is a post from me on this forum-let me see if I can find it for you..
Mike

Hi there,
https://www.the-t-bar.com/forum/9-mgf-tf-pitstop/98055-central-lock-door-wiring-colors/edit/198991

try this link, but there is a lot more on central locking for a TF

Mike

Hi Mike, thanks for taking the trouble, but the link gives a 403 error.
Kind regards
Theo

Try this one:
https://www.the-t-bar.com/forum/9-mgf-tf-pitstop/98055-central-lock-door-wiring-colors
or even:
https://www.the-t-bar.com/forum/9-mgf-tf-pitstop/98055
I get something that looks correct with these but the 'edit/198991' looks spurious.

I tested the motor by means of putting a 12 volt pulse to the wires and both lock and unlock works in that way.

I put in a brand new duracell 2032 in the fob, but no luck.

When I manually lock the doors I can unlock it with the fob.
Locking with the fobs used to lock the doors, and the alarm led started flashing rapidly, and after about 10 seconds started flashing slowly.
Now, when I use the fob and press the lock button, I hear the pektron relay clicking, doors do not lock, and and also no rapid flashing of the alarm led, however after 10 seconds the led does start with slow flashing.
When I lock the car with the key manually, also central lock does not work, the passenger door stays open, but the alarm does now work with fast and slow sequence.

So what I can rule out here : lock motor, fob battery, reception of fob signal (fob relays clicks both at pushing lock and unlock fob keys).
I have found a complete wiring schematic, next is to test the micro switches of the lock.

For the MOT the garage did some repairs on the wiring loom for the brake light in de boot, near the hinge the wire was broken. I checked the boot light, still works, but if the boot lock microswitch is somehow connected to the pektron, could it be that a broken wire is preventing the lock because the pektron thinks the boot is open ?

2 years ago I replaced all my pektron relays with good quality new ones, even made an how-to, so I am having a hard time believing this is again broken, but surely I will check, or just send the unit to Paul.
It is a weird fault, just appeared out of nowhere, worked fine, until just at once, could not lock the car anymore. No warning of intermittent failure.

BruceTF135 wrote:

Try this one:
https://www.the-t-bar.com/forum/9-mgf-tf-pitstop/98055-central-lock-door-wiring-colors
or even:
https://www.the-t-bar.com/forum/9-mgf-tf-pitstop/98055
I get something that looks correct with these but the 'edit/198991' looks spurious.

Just for your information, that link points to this same thread ...

tnjk wrote:

For the MOT the garage did some repairs on the wiring loom for the brake light in de boot, near the hinge the wire was broken. I checked the boot light, still works, but if the boot lock microswitch is somehow connected to the pektron, could it be that a broken wire is preventing the lock because the pektron thinks the boot is open ?

Break in the wires on the boot hinge can make havoc in the electrical system, but wiring is known and there is no connection from boot lock or boot light to central locking motors except they all pass through same Pektron unit, but within different circuits.
However, all is working as it should except pulse for door locking motor which is controlled by relay in the BCU.

you normally cannot here a SCU relay chattering., they are enclosed in a black box down in the central console and they are mini relays.
Have we clarified the type of TF you own?
From mid 2004 they have a SCU system and not a BCU.
The SCU system has the poor quality relays .
If you hear chattering noises they will be from the driver side door lock and in particular the super lock motor assy ( it has a rotating worm gear built onto it which fails )
The passenger side can also do this but usually results in a non opening or locked passenger door (very nasty to fix)
The side affect of a failed or failing door lock worm gear is that it can cause the SCU relays to fail prematurely if left too long.
You did well too make up a 12volt test assy ,this is what I did when my passenger door locked up and was then able to identify a SCU superlock relay failure and not a passenger door lock failure.
Hope this helps

It is a 2005 TF. I have removed the pektron SCU, no signs of damage to the PCB, also the relays look good. So I am going to send the unit to Paul technozen for diagnoses. In the meantime I would like to check the wiring harness, to see if the door lock wires indeed make contact with the pektron connector. I need a pektron connector pinout to do that. Looking at the test results it would surprise me if anything is broken in the wiring, but I want to rule out that part of the chain.
My idea of making a clone is useless to create a plug and play solution, because the key fobs are paired to a particular scu and cannot be paired to 2 scu's.
I would like to have a go at programming a pektron, therefore looking at a second hand pscan. I will put the request on the forum.

Last week I received the new relays for the pektron scu. I turned out that the central lock relay had failed, after just 2 years and about 5000km. So put a new one in, an all is working again.
Next job is fixing the radio. I will post a separate topic for that.