You can get stable voltage readings by connecting a green supply (fused
ignition) direct to the light-green/brown wire at the turn switch or use an
analogue voltmeter which generally copes with fluctuating voltages better.
Any voltage difference on the green/red and green/white supply wires
indicates bad connections back towards the common point i.e. the turn
switch, check the bullet connectors by the headlights and the multi-plug (if
you have one) by the steering column and it could also be a problem in the
Any voltage above 0v on the body of the bulb itself indicates bad grounding.
Check also the bulb holder body and the light unit base. The same volt rise
on all three indicates the light unit isn't grounding to the wing/fender
properly. You may have to scratch the paint round the hole then paint with
Waxoyl before fitting the light unit to prevent corrosion. Voltage on the
bulb body but not the holder indicates a bad connection between the two
which may be able to be cleaned up. Voltage on the bulb and the holder but
not the light unit base indicates a bad connection between the holder and
the base. With enough heat you may be able to get a blob of solder to
'take' and bridge the two rather than buying a new light unit.
----- Original Message -----
From: "Douglas Gaither" <email@example.com>
To: "mg list" <mgs@Autox.Team.Net>
Sent: Sunday, October 17, 2004 5:16 AM
Subject: Blinker prob
> I'm just putting my '66B back together. The directional indicator
> lamps are giving me some grief. The right indicator bulb works fine,
> but the left one, doesn't work at all. After a little investigation
> with a voltmeter, it appears there is a 4v drop differential between
> the left and right lamp sockets. The blinker blinks faster than my
> voltmeter can display, so there is a fluctuation of readings. But the
> right one fluctuates between 9.15v and 4.5v while the left one is 6v to
> 2v. I have narrowed the difference down to the lamp housing.
> Question 1: Am I misdiagnosing this?
> Question 2: Can I fix this either by replacing the lamp holder or some
> other modification?
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