Randell Jesup (jesup@cbmvax.cbm.commodore.com) laments:
>
> I'm (still) having some annoying problems with my turn signals on my
> '70 TR6. [...]
>
> It's not grounding at the rear, I tried running a wire from the rear
> light to the battery ground. No change. All lights burn equally brightly.
> I measured the resistance in each circuit (LF,LR,RF,RR), with the turn
> indicator bulb removed (since it interconnects the left and right). All were
> about the same - 1.5-1.7 Ohms from the flasher unit - which also means it
> isn't the turn signal switch.
The reason the left side is different from the right is because the impedance
on the left IS higher than on the right. You won't be able to see the
difference with your 2-wire measurements, since the difference only needs to
be around 0.2 ohms to be significant and your test leads probably account for
about half of what you measured above. But from what you have found, I think
the problem is actually before the flasher, and it IS affecting both turn
signals, however minimally on the right side.
> With engine off, voltage: at battery, 12.6-12.7. At flasher input:
> 12.0. At flasher input with left signals on (not flashing): 11.0 or so.
This is where I suspect the root of the problem is. You shouldn't be dropping
over a volt and a half between the battery and the "hot" side of the flasher.
A few tenths maybe, a half a volt tops. (This would work out to about 3/4 of
an ohm.)
> Wiring diagram: (roughly)
>
> - +
> i|----|i|i|i|---->fuses--->ignition switch---->(n-way connection with other
> dashboard circuits (stop lights, heater, voltage stabilizer, wipers)) ------
> --->flasher ...
I'd bet that this is where the problem lies: somewhere between the `+'
battery cable and the flasher. Try this: *Very* carefully, with the ignition
already "ON" and the left turn signal set to flash, run a jumper wire from the
`+' battery cable and the "hot" side of the flasher. If it doesn't cure the
problem, I'm out of suggestions. If it does, then you've got too much
resistance in either the fuse holder, the fuse (!), the ignition switch
contacts, or one of the many connectors. (The fuse should be the greatest
impedance in the circuit at about two tenths of an ohm.)
Good luck Randell!
Pat Vilbrandt Fluke Corporation Everett, Washington USA
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