260E central locking probs

[PaulW666]

Hi, I have just bought my first MB. It's a 260E it's like driving around in your armchair compared to my wife Rover.
I have a couple of questions...... the central locking worked when I first got it (using Scorpion alarm or key to open) but now the key will only open the door I use it in and the alarm will only arm/disarm the alarm. There also used to be a "whirring" sound when I got in after opening the doors, but that has stopped. Any pointers on where to start looking?

Thanks,

Paul.

 

[guydewdney]

sounds very much like the vacuum pump has gone down. merc central locking is vacuum controlled.

try looking in the boot fusebox for a fuse labelled central locking pump / system. pull it, leave for 30 seconds, and re-insert. this restarts the system....

guy

 

[grasmere]

"compared to my wife Rover"

Funny name for your wife - :lol:

 

[PaulW666]

sounds very much like the vacuum pump has gone down. merc central locking is vacuum controlled.

try looking in the boot fuse box for a fuse labelled central locking pump / system. pull it, leave for 30 seconds, and re-insert. this restarts the system....

guy

The only fuse box I have is under the bonnet on the drivers side with the relays sitting behind. I dug the pump out from under the back seat, is there any way to test the pump ?

The Haines manual said the pump might work off a relay, the only relays I have are the flasher, a big long relay (don't know what this does) and a small silver relay but the good old Haines manual doesn't tell you what they are.

 

[guydewdney]

ok - if none are labelled central lockiing or smilar - get desparate and pull the earth lead off the battery.


dont forget to do the radio code(s)

no idea how to test the pump.. sorry.

 

[talbir]

There's no need to search for a fuse if you have already dug out the pump.

Just disconnect the black 2-pin loom (3-pin loom if you have orthopaedic seats) from the pump and leave for 2 mins. Reconnect and try again.

With the black loom connected to the pump, remove the other 3-pin clear plastic plug from the pump (which has a blue, green and yellow wires coming out of it). Connect a wire to any point which is ground on the car (you can also use the negative terminal on the battery) and connect the other end of this wire to any of the 3 pins on the pump. If no sound from motor, then try connecting the wire to +12V, and then attaching the +12V wire to each of the 3 pins. If no sound from pump, then pump is dead. If there is sound, but locks are not locking, then there maybe an issue with wiring at the actuators or the pump itself - or that one of the yellow vacuum pipes is disconnected or leaking.

Basically, the pump is activated by a single wire(the blue one). This wire when earthed locks the doors. The same wire when fed +12v unlocks the doors. The green and yellow wires come from the pass door and boot locks, so if the car is locked from those points, then all locks are locked. It's hence called a multi-point locking system.

Ensure the yellow vacuum pipes are firmly attached to the pump. If pump whirring goes on for a long period of time, this indicates a leak, either from one of the pipes, or one of the actuators (boot, doors and petrol flap).

Give us a shout if you need any further info. A good used pump is about forty quid from a good MB breaker, ie. Mercman in Southampton.

 

[PaulW666]

There's no need to search for a fuse if you have already dug out the pump.

Just disconnect the black 2-pin loom (3-pin loom if you have orthopaedic seats) from the pump and leave for 2 mins. Reconnect and try again.

With the black loom connected to the pump, remove the other 3-pin clear plastic plug from the pump (which has a blue, green and yellow wires coming out of it). Connect a wire to any point which is ground on the car (you can also use the negative terminal on the battery) and connect the other end of this wire to any of the 3 pins on the pump. If no sound from motor, then try connecting the wire to +12V, and then attaching the +12V wire to each of the 3 pins. If no sound from pump, then pump is dead. If there is sound, but locks are not locking, then there maybe an issue with wiring at the actuators or the pump itself - or that one of the yellow vacuum pipes is disconnected or leaking.

Basically, the pump is activated by a single wire(the blue one). This wire when earthed locks the doors. The same wire when fed +12v unlocks the doors. The green and yellow wires come from the pass door and boot locks, so if the car is locked from those points, then all locks are locked. It's hence called a multi-point locking system.

Ensure the yellow vacuum pipes are firmly attached to the pump. If pump whirring goes on for a long period of time, this indicates a leak, either from one of the pipes, or one of the actuators (boot, doors and petrol flap).

Give us a shout if you need any further info. A good used pump is about forty quid from a good MB breaker, ie. Mercman in Southampton.

Thanks for the advise.
I contacted Mercman today regarding a new pump. £50 + VAT better than the £300 the main dealer wanted. I'll check it out to make sure it is the pump first.

 

[PaulW666]

Well that settles it..... the pump's dead