On your Uno - you need to take the light units off and spray all the contacts with contact cleaner. With the lens off and the hazard flashers going, wiggle the bulbs to make sure the connections are wiggle-proof. I bet you've just got a loose/corroded bulb holder or possibly the plug to the rear light cluster.
Sounds like your stalk switch (presume it's a Mk2 Uno with stalks on steering column) is having some problems: otherwise, there's little explanation for why the washers would be dependent on the wipers.
On the headlamp issue, I agree with D4NS, most likely to be the ground for the headlamps, and also check the bulb plug itself. But on the other issues, check the above points first before you find the grounds. (Actually, the rear light unit plug is usually the cause of bad grounding, so I suppose D4NS is right...) You should be able to get those things working without too much trouble.
See if you can get the stalk switch apart - if not, then spray some of that contact cleaner aerosol inside it and work all the switches.
My 1987 Lancia Thema took the biscuit.
It had a 'check panel' of the best kind, the one with an LED for each of the front-left, front-right, rear-left, and rear-right sidelights. There were also other LEDs for the oil level, coolant level, etc. etc.
The front-right and rear-left sidelights warnings used to 'light up contemporarily' (as the handbook put it) when driving at night, but only sometimes, and only for a little while. The sidelights themselves were fine. After they had been on for a while (and the red CHECK light flashing in the instrument panel), the system changed to flash the LEDs instead, while the CHECK light stayed on. Until - the fault cleared. Sometimes, all would be well for several hours, sometimes only for five seconds. Then, the next time, the CHECK light would start flashing again. Keeps you company on long trips. Mesmerising if the handbrake is also on - the lights flash at different rates, so they get in and out of time with each other.
Once, I checked the oil level, using the dipstick. (I know, I don't know what came over me.) It was fine, but from that point on, the oil level LED would show up from time to time. There was no logical connection, since the sensor is not part of the dipstick. When I tried to fix it, I found that both the sensor AND the check panel were faulty all along, so that most of the time the two faults cancelled each other out and caused no warning.
The coolant level sensor registered 'low' when I bought the car: because the float didn't float. After filling with antifreeze, it did! So the 'check panel' was an indicator of antifreeze strength.
Central locking is always good for a laugh if the wires to the front door motors break near the door hinge. When the system tries to lock the doors, one door lock stays 'up', so the system reads that switch as 'up' and decides that the doors are being unlocked. It thus unlocks the doors. Under ideal circumstances (broken wires on both sides) you can get a situation where the back doors only continously lock-unlock-lock-unlock...
My FIAT Croma had even more exciting electrics, due to intervention by the last owner (a builder). The reverse lights didn't work. One bulb blown, one bulb missing. A simple fix? With two bulbs in there, the check panel indicated 'automatic transmission overheating'. The cause? Reverse light switch wires connected correctly to the shifter inside the car, AND also connected to temp sender on transmission - oops! Sometimes, it's OK for plugs to be 'spare'. The one in the engine bay was for a different transmission type with the reverse light switch on the transmission.
Pulled the windscreen washer one day, and SNAP went the fuse for the wipers. That was because the wires at the front of the car (for the headlight wipers, not fitted) had been helpfully plugged into the earths for the headlight wipers. Just a hint - if the wire colours don't match, think twice before you plug them together, OK?
That car also had dire check panel faults saying that doors were open when they were closed, etc. Sometimes, these things can have so many simultaneous faults (switches, wiring, etc.) that you go mad trying to fix them.
Even my Alfa 164 has had a few clangers. Switch to high beam at night, and the handbrake warning light glowed briefly. That was a poor ground at one headlight (melted plug). One night, I almost backed into a concrete post. The very sharp application of the brakes at the last split second locked all four wheels (ABS doesn't work at slow speeds) and caused the engine to stall (it's an automatic, so that was surprising enough) but also, all the electrics went dead.
By the moonlight, I could just slide my little finger between the bumper and the concrete post. After a few minutes of turning the key on and off, everything came back to life and I drove home without problems.
-Alex
