Hi folks, I've just come in from trying to find the reason for no dip beam on my 1988 2CV. I've used a test lamp on the switch; Switch off - No Power. Switch on V - I'm getting power on one contact/wire with switch pulled back (side/tail) and power on a second contact/wire with the switch in the forward position. With the switch in R position, I get power on the same two contacts in the forward position. With the switch in R and towards the driver, I get no power to the second contact, and power to the third contact. Now I'm assuming the first contact is side/tail, the second contact is dip beam, and the third contact is high beam. I seemingly have no power to the dip beam contacts at the headlamp bulbs. I've checked the connections under the bonnet and nothing is looking obviously loose/disconnected. I'd appreciate any pointers/advice. Cheers, and tah very muchly.

Bit of an update; I checked out a diagram of the wiring and discovered there's actually 5 electrical connections on the back of the lighting/horn control. I noted the fog lamp is powered through the same contact as the dip beam so decided to check if the fog lamp illuminated when the switch is on the dip beam position, which it does. I then tried it with the main beam on. I've now got the problem of the main beam is illuminated on dip as well as main position on the switch, including on the V position!! Bizarre!

With that sort of weirdness, I would be checking out the grounds first. With bad grounds, electricity tries to find another route. Possibly in this case, back through the fog lamp.

Edit
Also, Though the dip may work on the same ground as the main beam, A poor ground may stop the main beam working, but allow the lower wattage dip beam to work if it will not pass the extra amps off the main beam.

Thanks Roger. Can I assume that the switch is functioning as it should be? I'd imagine if the roller contact inside the body is corroded/worn/damaged then I'd get no power at the wire and the fog lamp will not work.

Sorted. The issue was traced to a bad connection at the bullet connector on the headlamp bar. Yesterday afternoon I took the car out for a roughly 40-mile run and all was well until the last half-mile when the indicators and fuel gauge stopped working. That was very quickly traced to a poor bridge across the fuse for the indicators/fuel gauge/wipers which I've now rectified.

Cool
Well done