Good point SuperUno!
I always fondly believed that the Mk2 Uno rear lights were perhaps improved over the Mk1's, maybe in the style of the aesthetically-similar Tipo rear lights. Then again, maybe not.
With the Mk1 rear light cluster:
- Take off lens and spray contact cleaner at the bulbs and holders, working the bulbs in and out a few times. Tighten the bulb holders. Wash inside the lens if you're feeling benevolent.
- Remove 2x press studs for 'carpet' inside boot, pull furry plastic back to expose plug. Unplug and tweak the pins with a fine screwdriver if necessary to ensure a tight contact. Spray with contact cleaner, work in and out, etc.
Above two steps take maybe 10 minutes per side and solve most problems to some extent.
If you have more time... perhaps take a while to improve on the design and construction of these luminaires and increase the emitted lux...
Bulb holders, plug contact pins, and wiring circuit are all made from galvanised steel rivetted onto phenolic board - a surprising choice of materials. Outside contact of the bulb holder makes contact only by being crimped in place onto the wiring circuit. The plug on the back frequently works loose and the pins become delicately coated in a white powdery corrosion.
Test the earthing by switching on tail-lights, rear fog lights, reverse lights (engage gear with ignition on), and THEN switch on the hazard flashers (gives everything a real workout). If the other lights are flashing as the indicators flash, then the earthing needs improvement. You could also check the voltage with the bulb in place and glowing... I found a record low of 8.5V on one of my Unos. Fuses may blow also as the current back-feeds into the other circuits. Possible solutions:
- Add an earth wire to the circuit track, with a hole drilled through the track and into the light unit, for a self-tapping screw. Use another self-tapping screw to fasten the other end to the steelwork behind the light.
- Solder all the bulb holders onto the circuit tracks. This can be achieved with 'Duzall' green bottle or similar flux, and a high-powered soldering iron that you never expect to use for electronics work again.
- While you've got the cluster apart, consider spray-painting the black plastic backdrop with shiny silver paint. It really does make the lights brighter. Of course, the optical engineering seems to rely on the 'bulb in a box' principle, with no thought given to attaining parabolic reflector profiles except for the rear fog lights that benefit from a small piece of chromed rusty tin (which must have been needed to meet some minimum standard...)
-Alex
