I put up with that leaky situation for way too long, spending many an hour reading about solutions and hatching a plan to convert the sunroof operation from manual to electric. Taking the headlining out to trace and cure the leak would provide the perfect opportunity to convert the sunroof to electric operation and I began to plan combining both tasks.
Do the Research.
I found the pages of Rave invaluable in planning what to do. All the components are described, identified, located and the wiring diagrams have all the answers if you stare long enough!
Lots of advice and opinions about the conversion to electric can easily be found on the web pages. All of this web stuff is good to read but you do need to pick and choose reference points and you just cant go wrong with Rave.
The Essentials
Two motors, a little box of tricks, the factory wiring loom and a set of fitted switches are all needed. Fitting the components to the vehicle is easy enough. It really can be a case of plug and play.
Even the final hurdle of switching the BCU to operate and control the circuit can be by-passed if needed. When I was planning the work I did not have a Nanocom to interrogate the BCU and this stage troubled me, but as I worked through it, it became obvious that a direct 12v supply to the power loom would be another option. In the end and by the time I got around to the work, I had saved the pennies and bought a Nanocom.
The Motors
LR part number - EGQ100230
These small compact and powerful motors are readily available second hand. Their design and connectivity remained virtually unchanged throughout the entire Discovery D1/D2 production run. I would not be surprised if these motors can be found in other vehicle ranges as well.
Despite having well sealed cases they can suffer from water damage caused by the leaky sunroofs. Combine that with long periods of non-use and the harsh environment of the roof space and the internals can seize up in extreme cases. However, with a bit of care and a good clean even the worst offenders can be brought back to life.
The motor bodies are secured to the sunroof frame by three bolts. The locating holes are already present on every sunroof frame. It is important to source the mounting bolts as one is a bit unique. A good parts dealer should know this and supply the bolts with the motors.
Timing Marks.
There is a micro-switch mounted near the edge of the red plastic disc and indents on the side of the disc control the operation of the motor as it revolves with the cogwheel. It is important to get this 'timing' correctly set before fitting the motor to ensure the sunroof will open/tilt correctly. This is easy enough to do before the motor is attached to the frame...
Seized Motors.
I sourced my sunroof motors from the Internet and when they arrived, I tried to hand operate the mechanism by gripping the cogwheel and twisting it. They would not budge and it led me to fear that they where seized. I then remembered the Allen key recess on the base of the drive spindle.
Fitting a suitable Allen key in there did shift the motor but the effort required was more then I would have expected. However, attaching a 12v supply to them soon kicked them into life. A spare 12v 45Amp car battery was used as the power source. The motors are power hungry and any current below say 15Amp might not kick them into life. When fitted to the vehicle loom, their supply circuit runs a 30amp fuse.
At the time, I had already read up about fixing a seized motor. There are a couple of excellent illustrated tear-downs currently on the Internet and they can easily be found by a Google search for 'Discovery 2 sunroof motor'. The post by 'Bigdave' on 'Landyzone' has an in-depth step by step photo guide....
After a strip-down and a good clean-out of the mechanism, it should return to life. Although my motors were both functioning, I decided to open them up for a peep inside. All looked OK and there was no signs of water ingress so I reckon they have had an easy life so far.
The Electric Sunroof Wiring Loom.
Research on line about the presence of the elusive loom throws up some differing opinions. Obviously it will be present if the vehicle already has electric sunroofs fitted, but it also appears that the loom was sometimes fitted even if the sunroof operation was 'manual'. This seems to be the case for the D1 and the D2. However, when the 'facelift' D2 model appeared in 2002, it seems that the loom was omitted unless the vehicle was fitted with electric sunroofs?
The loom itself is neatly self contained. One end has all the relevant connectors for the motors, switches and control box and the other end has a single plug that connects to the main vehicle harness. This modular design makes its installation easy, it also makes it's omission an easy cost-cutting measure.
Hx is a 'facelift' 2002 model D2. So the first task was to find out if it already had the loom or not...
There are two ways to do this.
(1) - Remove the overhead console and stare into the Abyss! If present, all the connectors will be readily apparent. There will be a mixture of blue, green and white coloured connectors..