With time the laser on the satellite navigational unit can get dirty, the spinning disc causes air to circulate over the laser, thus leading to dust building up. You'll just get the dreaded "error reading disc". Now this might not actually work for everyone, as there is a possibility the issue lies with the disc itself or the laser, which will require replacement.
This guide is relativity straight forward and will take you around one hour to do at home, including taking out and fitting back into the car
I have used eternal422's images from his "X-Carlink How-To", I hope no one minds
You will need:
MAKE SURE THERE IS NO DVD IN THE DRIVE!
- Trim Removal tool or decent fingernails
- 10mm hex bolt screwdriver adapter (I think)
- Precision cross point screwdriver set
- Isopropyl rubbing alcohol or the missus nail varnish remover
- Ear buds
1. Lift the gear-stick gator / trim using a trim removal tool (I just used my fingers)
2. Once it's out, disconnect the heated seat switches.
3. Remove the ashtray.
4. Remove the two bolts underneath the ashtray.
5. Pull the ashtray assembly out, be careful, as you will have to disconnect the cigarette lighter and the bulb.
6. Disconnect the wires attached to the lighter socket, twist the ashtray bulb a quarter turn to remove it.
7. Remove the 2 screws underneath the ashtray assembly. These hold the bottom of the sat nav panel in place.
8. Pull the trim panel towards you, easier to do with fingers than a trim removal tool. There are 2 clips holding it in place at the top, you might have to use a bit of brute force an ignorance here.
9. With the DVD drive exposed, remove the 4 bolts holding it in place:
10. Disconnect all the wires at the back.
11. Remove the brackets from either side of the DVD, make note with a marker which holes they screw into (there are three positions). Once out, move to a dust free environment, most kitchens or garages should suffice .
12. With the drive out, remove the two screws on the back of the chassis. Remove the lid from the top of the chassis sliding it back away from the front.
13. Remove the four screws keeping the top layer in the casing, a magnetic screwer driver really helps here.
14. Lift it carefully disconnect the ribbon cable, there is a small plastic clip that holds it in place, push this downwards towards the ribbon cable to release it.
15. With just the top layer out, remove the screw holding the disc balancer in place (this is the smallest screw, DO NOT LOOSE IT.
16. This is the most intricate of dismantling, remove the top and bottom plates including the plastic centre.
17. this should expose the centre of the drive, from here you can see the laser:
18. Apply and small amount of rubbing alcohol onto the earbud (do not let it drip) and carefully wipe it clean, you should not need to dry it as it should evaporate.
The hard part is putting it all back together, place the small centre lower metal plate into position and turn the unit upside down and position it into place whilst holding it and looking up at the unit.
Keeping it in place with your finger place the circular plastic part in the top part of the plate and screw into place very loosely but at 90 degree angle, what you're actually trying to do here is prevent the bottom part from falling into the chassis. You'll know what I mean once you have it open.
Line it all up and wedge a screwdriver to the left of the bottom plate to keep it upright, unscrew the top plate from the bottom plate and carefully fit it correctly under the metal lugs. Carefully screw it back in and it should all be where it should be.
I'm sorry there are no pictures for this, but this is because It was a two hand operation, left hand to hold the bottom plate to the chassis with a screwdriver and the right hand to screw the top plate to the bottom plate
After that, just attach everything back together and ensure to clip the ribbon cable back into place.
I hope this is useful to anyone out there looking for a quick fix !