I have an strange problem with the indicators on my Clubby.

The front left indicator isn't working, but rear left is. The right hand side indicators work fine. Seems like a relatively simple problem until you add the second symptom:

The left side rear indicator (and maybe front as well, I don't know) flashes sometimes (maybe all the time?) when driving. It just flashes once, then stays off until the next flash, which is probably about 30 seconds later.

I checked voltages and resistances at the front indicators and they seem ok. I checked voltages at the indicator assembly on the steering column and the left side seems to be getting a little less voltage. This might be because my multimeter is digital and may not be able to react fast enough to display it properly. I also checked voltages at the front indicators with the park lights on and they seem ok.

The car is stamped as a '76, but I think it was actually made in '75 based on the master cylinder type. I have been using the wiring diagram of a '75, but it shouldn't make much difference anyway. All the rest of the electrics on the car seem fine.

If all voltages and resistances are ok, have you checked your earths?

Random off and on could result from a loose earth bumping around while driving.

I would put my money on a bad earth on the front left indicator.

90% of electrical problems seem to be related to bad earths, and the added bonus of the car being 30 years old and british design means time and rust/corrosion don't help them out at all.

I'd be checking the front bulb contacts and mounting points for the indicator housing to body etc.

I just checked the earths and got the following resistances.

Front left: centre of bulb socket to body - 1.5 Ohms
Front right: centre of bulb socket to body - 3.0 Ohms

I also checked the body-to-engine earth strap while I was at it - 10 Ohms

So I guess its not a bad earth then?

A red hot favourite would be to look at the front and rear indicator light socket. the bulb might be shorting the parker circuit to the indicator circuit if the flashing is coming on at night (How else did you notice it?).

The bulb may be loose or you tried to put the wrong type of bulb in the socket.

Try reseating the bulb and try again.

Also look at any recent wiring work you have done. This is the most common sources of issues and accidental damage. The ohms measurements you are getting is because you are measuring through the other bulbs in the circuit.

Earths don't cause lights to flash, they stop them from coming on instead. Unless you have a double fault, it will not be an earth.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Hi Check all of the bullet connectors in the wiring loom. I had a similar problem with a 67 deluxe recently with the connections being slightly loose. Also the 10 ohms for the earth strap seems a little high? I would have expected 1 or 2 ohms?

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1969 Cooper "S"
1967 Mini Deluxe
1973 Clubman Van (the fleet spare)
1978 ex 1275 LS ("Wizard" Eaton Supercharged)
2015 HSV GenF GTS(occasional drive & tow car)
2019 MINI F55 Cooper S

I swapped the bulbs from side to side and tested and found out that the bulb isn't working The filament is still intact, but it isn't working. It must have been working at some stage because I noticed the flashing from the front indicator before.

So the blown bulb still doesn't explain the random indicator flashing. This has been happening at night and during the day. I have noticed it at night, and other people have been following me before and commented on it during the day. It is pretty erratic, not regular.

The light sockets are all fine - not corroded or anything. I haven't done any electrical work on the car since i got it a little over a year ago.

michaelb - The earth strap resistance might be a bit high because the points i was using for measuring it were a bit dirty. I don't think it is anything to worry about though.

Good work on finding your dodgy bulb.

I still reckon then that it will be the bulb. it's probably got something going with the soft lead contacts on the back, or it doesn't align properly when it is seated in the socket. But check the back of the socket for bent contacts, stray bits of wire or what-not.

try a new one, avoid the supercrap ones as they are very dim and are pretty shite. look for a good brand.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Ok, I am off to get a bulb shortly. The bulb still wouldn't cause the flashing when I am driving would it?

It very well might, if it shorts between the park and the indicator circuits (parkerss would need to be on however).

But deal with one fault at a time and get the other one if it still exists after that.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

I just replaced the offending globe and unfortunately it didn't fix the problem but at least the indicators are working

Now isolate the front from the back and see if it still happens.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

OK, I will have a go at doing that next.

EDIT: scratched my second comment because I re-tested and it was ok.

I haven't had a chance to isolate whether it is front or back, but I have noticed it before when driving (front) and other people following me have noticed it before (back). I will confirm this when I get time.

I also noticed when I was driving it a short time ago that the left indicator didn't work one time - I flicked it on and nothing happened. I tried later and after a few goes I got this to happen again, so I have a suspicion that there is something wrong with the switch.

Also, if my understanding of the circuit is correct then the only way to turn on the indicators is to bypass or short out the switch, or have a short of a current carrying wire into the circuit after the switch somewhere. The short could cause something else to not work properly which doesn't appear to be happening, so the switch is my prime suspect at the moment

Indicators mechanisms will alway give you the shits. I have found that the simple rocking motion of the switch back and forth will damage the copper wire terminations onto the switch mechanism itself. You could take the column shroud off and have a look inside. Look for loose wires or connections on their last strands.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.