Oh dear. I've been working with this stuff for 40 years, playing with it
for a dozen or more before that. I'm going to try and explain what I mean,
ignoring the offensive attitude and language, even though you may well not
bother reading it.
Draw out the circuit in a straight line, from earth, through the battery,
manual and gearbox switches, the solenoid, to earth.
The voltage all the way along circuit from the battery 12v terminal to the
solenoid terminal in a working circuit with switches closed will be battery
voltage. It doesn't matter whether the solenoid is passing the correct
current, is operated and doing its job, or if the solenoid has an
open-circuit in the windings or to earth, you still have battery voltage at
the solenoid terminal. A voltmeter will only show a break in the circuit up
to the last point you can connect it to, which will be the wire leading in
to the solenoid. You can have a break inside the solenoid winding, or its
earth connection, and the voltmeter won't show it. You can't get in to the
solenoid to test it without removing it, and this is an intermittent fault
remember. By the time you have taken it out the fault may have 'repaired'
itself again, and in any case you have broken the earth connection to the OD
body so can't test that anyway. It means getting under the car
with tools to remove the solenoid, a waste of time if the fault proves to be
electrical elsewhere. A resistance test will show if the solenoid winding
and its earth connection are correct, but you can only do that with the
power disconnected, when the OD will be disengaged anyway. The only way you
can be sure that the circuit is *complete and drawing the correct current*
is with an ammeter.
I'll say again, simply connecting an ammeter to a parted connector in the
engine bay, driving along waiting for the intermittent fault to occur again,
and looking at the ammeter when the OD stops working is the easiest way of
proving whether the fault is electrical or not.
It's a two-connection, real world monitor that allows the OD to operate
normally, that you can leave in
place until such time as the OD drops out again. The only thing to
bear in mind is that the connector you have parted may have been the source
of the bad connection, in which case the OD probably won't fail again due to
the disturbance,
ammeter connected or not.
Only when you have proved current isn't flowing when it should be, would you
then test along the circuit with a voltmeter, *which needs the ammeter to be
left in circuit to be sure it hasn't repaired itself again*, to see where
along the circuit you stop getting voltage. If you can get all the way to
the connector on the wire leading into the solenoid and still have 12v, but
no current, then the problem is either with the solenoid or its earth, but
you can't be sure which.
PaulH.
----- Original Message -----
Your reply shows that you have no idea what you talking about.
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