Hi everyone. I have mk 1 Octavia which is driving me crazy!

Main problem, I can no longer use the key fob to lock the central locking. I have changed the battery in the fob about a year ago, and if you push the button on the fob you can see the led flashing on the fob, so I think the battery is fine. If I unlock the car via the boot lock using the key, it work fine. If I unlock the car using the key in the drivers door lock, 15% of the time it will unlock all doors / boot, but 85% of the time it will just unlock the drivers door, i.e I can not hear any motors whirring and no interior light comes on, the key simply mechanically unlocks the single door. This would suggest to me the locking unit in the drivers door needs changing? If that is right, how does that unit "pick up" signal from the fob? Does the replacement need programming in some way, if not surely any Skoda fob would open the central locking? I also have never been able to lock myself in the car using the switch on the drivers door panel, but I have lived with that!??

Second problem. Only occasionally, the fuel guage will suddenly drop to empty and the low fuel light will come on. This can last for an hour or so, or the guage will slowly return to normal in a few minutes? This is just annoying and sounds like a connection, but where do I start?

Any help would be gratefully received!!

Mark.

Hi everyone. I have mk 1 Octavia which is driving me crazy!

Main problem, I can no longer use the key fob to lock the central locking. I have changed the battery in the fob about a year ago, and if you push the button on the fob you can see the led flashing on the fob, so I think the battery is fine. If I unlock the car via the boot lock using the key, it work fine. If I unlock the car using the key in the drivers door lock, 15% of the time it will unlock all doors / boot, but 85% of the time it will just unlock the drivers door, i.e I can not hear any motors whirring and no interior light comes on, the key simply mechanically unlocks the single door. This would suggest to me the locking unit in the drivers door needs changing? If that is right, how does that unit "pick up" signal from the fob? Does the replacement need programming in some way, if not surely any Skoda fob would open the central locking? I also have never been able to lock myself in the car using the switch on the drivers door panel, but I have lived with that!??

Second problem. Only occasionally, the fuel guage will suddenly drop to empty and the low fuel light will come on. This can last for an hour or so, or the guage will slowly return to normal in a few minutes? This is just annoying and sounds like a connection, but where do I start?

Any help would be gratefully received!!

Mark.

Pretty sure your Central Convenience Module has failed.

Fuel tank sender could be the problem with your gauge.

Pretty sure your Central Convenience Module has failed.

Fuel tank sender could be the problem with your gauge.

Hi, "Central Convenience Module"? where is that located? Any idea of cost at all? Many thanks.

check the wiring in the joins of the doors for any breaks/ bare wires first

When you unlock using the boot, all the door except the driver's side are opening, which shows the Central Convenience Module is working correctly. It is accepting lock/unlock inputs and sending lock/unlock commands to the doors.

The most likely cause is the control unit that is part of the driver side door window motor. Unfortunately, it is an integral part of the window motor so the motor will have to be replaced. It controls the window, the mirror heater, door lock, flashing LED, interior light and the central locking switches in the door arm panel. This is why you have no drive to the door lock motor and the interior light doesn't work. It is possible that it is a fault in the wiring, but it would take multiple faults to create your symptoms.

Are you saying you have remote central locking?

Is the keyfob a Skoda one?

Just because it has a skoda badge doesn't mean it is OE. If you have an aftermarket remote central locking unit, it is often wired to the driver side wiring to mimic the actions of the central locking switch, so unless the above is fixed the remote won't work.

The fuel sender most likely is broken. When the guage has dropped, bounce the rear of the car up and down. You will probably find the guage briefly returns to the correct reading.

ive seen this issue lots and the fault has been a damaged cable from the window motor thats why i say check the wiring

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I'd agree that the central locking problem is most likely with the driver's door cabling or connectors.

Fuel tank issue is probably the tank sender, or the connections there. I hope there are no issues with the other gauges though. It there were, it would suggest a problem with the instrument panel PCB.

Many thanks for taking time to respond! When I unlock the car from the boot lock, ALL doors unlock fine, interior light comes on etc.

I replaced the drivers door regulator earlier this year, but not the motor, so maybe a poor connection? I just tried sitting in the car and locking the car with the key in the door lock (with the window down) car locked all doors (this time!) and I can use the switch on the drivers door to unlock all doors, but this switch will NEVER lock any doors?

The key fob is definetely genuine. The fuel guage problem hasn't happened for weeks now, which is making me think it must be a connection problem?

I think it might be time to pull off the door trim and have a play?

When you unlock using the boot, all the door except the driver's side are opening, which shows the Central Convenience Module is working correctly. It is accepting lock/unlock inputs and sending lock/unlock commands to the doors.

The most likely cause is the control unit that is part of the driver side door window motor. Unfortunately, it is an integral part of the window motor so the motor will have to be replaced. It controls the window, the mirror heater, door lock, flashing LED, interior light and the central locking switches in the door arm panel. This is why you have no drive to the door lock motor and the interior light doesn't work. It is possible that it is a fault in the wiring, but it would take multiple faults to create your symptoms.

Are you saying you have remote central locking?

Is the keyfob a Skoda one?

Just because it has a skoda badge doesn't mean it is OE. If you have an aftermarket remote central locking unit, it is often wired to the driver side wiring to mimic the actions of the central locking switch, so unless the above is fixed the remote won't work.

The fuel sender most likely is broken. When the guage has dropped, bounce the rear of the car up and down. You will probably find the guage briefly returns to the correct reading.

After my issue on Sunday ( http://briskoda.net/forums/topic/176736-help-only-the-boot-will-lockunlock-all-4-doors-do-nothing/page__p__2130431__fromsearch__1entry2130431 ), I know how you feel!

Mine was the power line for the central locking going to the drivers door, shorting on the body and blowing the central locking (4 doors only)/fuel cap fuse (fuse 38). The boot is conveniently on a different circuit, so that was the only thing that unlocked and locked with the remote fob.

With fuse 38 removed, the drivers door control panel still works (opening/closing all windows and locking/unlocking the boot only). What doesn't work is the deadlocks, filler cap, door LED and central locking of the four doors (with remote, key or interior switch).

If your boot lock unlocks and locks all the doors perfectly, then there must be power to all the locks.

I don't know much about the central locking so I can't help much, but rwbaldwin diagnosed my fault pretty accurately!

Suppose you could have a broken wire in a similar place to mine. I guess there's a signal wire that tells the CCM when the drivers door has been locked/unlocked with the key/switch, which in turn sends a signal to all the other door lock modules. Does that make sense, or is it even feasable?

Where is the remote central locking receiver located anyway? Drivers door or dash somewhere?