headlights pop up but wont go down

[FI Spyder]

The motor does only go in one direction with sensors (contacts) in the sealed (hopefully) block by the mechanism. Re: connections, as they are exposed, they will get dirty (corrode). Use contact cleaner. Not all contact cleaners are created equal apparently. One in particularly was recommended (search the forum). It's good if you can get a small brush in the circular portion on the connections, I use pipe cleaner, not as stiff as I'd like but better than just the chemical action. That connection can expand not giving a tight connection. Connections can back out of the nylon casing as there is a little tab (tine) that prevents this by either breaking or more likely pushed back in so it doesn't engage the casing which is what prevents it from backing out. There is a weak point where the metal connector grasps the wire were the wire can break, maybe just partially, hard to see visually. Connectors can be bought or in a pinch can sometimes be opened up (not easy) and reused. Some people like to solder the wire to connector to prevent this from happening again. You can get a small tube of dielectric grease (grease that doesn't conduct electricity, seems counter intuitive but prevents electrolysis) to prevent recorrosion. The lower adjustment is made first. The upper adjustment is a movable upper stop that is set such that the motor drives into it (by 1 1/4 to 1 1/2 turns of the stop). This prevents the light from fluttering in up position. The weight of the unit is counterbalanced by a torsion spring. The unit should be clean with moving/touching surfaces cleaned and greased so it doesn't cause excessive friction into the picture. The contacts in the block have to make and break properly so power the the motor starts and stops at the right time so it doesn't over shoot and/or continues driving. Adjustments are in the OEM. There are other parts of the circuit (relays etc.) but the pods are at the dirty end of the car with all the road detritus coming up at them so I would pay all attention to this area first.

[saabfast]

If you are in the UK I use Contact Cleaner and Silicon Grease from Maplins, seems to work OK.