Discovery Central Locking / Electric Windows

[repton]

If a Disco (S reg 300tdi Disco1) central locking is only opening 3 of the 4 doors where would be the first place to look to try and work out why it isn't working on the 4th one? It's the drivers side back door if that makes any difference.

Also if the rear windows are only working intermittently what might that be?

TIA,
Paul

[Bo]

Could be a broken wire in the door hinge or a faulty actuator but its more likely the actuator. Easiest way to check is remove the door card and unplug the actuator. It is a really simple system where changing the polarity of two wires either locks or unlocks. Use a 12v feed straight on the the actuator plug and see if it locks and unlocks. If not its the wiring so start to trace it back, checking as you go.
The windows is probably water in the control unit. Black box passenger side foot well behind the glove box. Empty the glove box and lift the two spring loaded stays that limit its opening, up out of the slot. This allows the lid to open fully. You will also need to remove the trim under the glove box as you look up from the foot well.
The front clips out of the electrical control box and the circuit board slides out.
Check it for staining. Sometimes you are luck and can get it to work by drying it with a hair dryer and clean the fur off but usually they are toast and need a replacement.

[repton]

Thanks Bo, that gives me something to work with.

Next question - what kind of sealant is best to seal up sunroofs?

This is the vehicle btw, just bought it to replace the one Lindsey parked on its roof: http://www.ebay.co.uk/itm/251473348377

Seems spot on so far, drove back from Middlewich without a hitch yesterday. It has plenty of rough edges but a lot of them I can fix with bits from the smashed up one (like the central locking hopefully if it is the actuator... maybe not the windows as the back windows on the old one were temperamental too).

Ta,
Paul

[Bo]

Usually worthwhile checking why roofs leak. Common cause is the drains are blocked or the pipes have come off. First one is an easy cure, use something thin and flexible to unblock then. If they have come off you can drop the headlining at the edges and get your hand up. If neither of gage above work for you a good quality windscreen seal will do the job, just make sure you clean off all the old first. Mine leaks and I don't even have a sunroof so check top of screen and around rear Alpine lights.

[Matthews]

Sunroof out and 1/2 tube of stickaflex round the frame where it goes into the roof ( standard thin foam seal between frame and roof falls apart ). Usually it's the motors in the locks on the door that fail (my rear drivers door is the same , locks but won't unlock), check master and centre console switches for windows as they often get wet (leaky sunroof) or get stuff spilled in them .
Matthew

[repton]

I've fixed the leccy windows problem. Turns out it wasn't water in the control unit, it was a dry solder joint. Have a look at this page for more details:

http://www.landyworld.co.uk/discovery-t ... c-windows/

I took the control units out of both the smashed up and "new" Discos and they both had a dry solder joint where that webpage shows, so it looks like it's a pretty common issue.

Not had a chance to look at the door lock or sunroofs yet. Sounds like I need to wait for a dry day for the sunroofs and take them both out and reseal them properly. Someone has already had a go with some silicon but it clearly hasn't had the desired effect...

Paul