Morris Minor Owners Club

The offside rear flasher doesn't work anymore, front is fine and it flashes double quick.

It isn't the bulb, I've checked that, but there are only a few volts reaching the back of the car. A voltmeter pulses at around 5 or 6 volts when connected between the earth and supply to the bulb holder, but I'm pretty sure its not a bad connection in this area.

I think it must be the flasher switch on the column, but I'm surprised that both bulbs are connected to it individually.

Can someone confirm this and tell me what size the steering wheel securing nut is please??

Hello John,
I'll start by explaining how the indicators work, from an ignition controlled fuse a supply is taken to the flasher relay, then out to the indicator switch which in turn feeds both front and rear lamps, the flash rate is determined by the current drawn through the relay, and is normally two x 21 watt lamps.
So if one lamp is flashing very quickly and the other side both work normally, the most likely fault is a partial short of the cable to the rear lamp. The low voltage at the rear would also seem to indicate that. Depending on the type of meter you are using you should see a swinging voltage. Normally with one lamp inopperative, the flasher relay just stays on as there is insufficient current flowing through it to heat up the bi metallic strip that causes the flash. A very basic device. Forget all of the above if you have an electronic relay fitted which sometimes happens if someone fits a towbar.

Alec

Now fixed, thanks Alec, turned out to be a dodgy earth at the rear