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Re: Fried wiring

To: "MonteMorris" <>, "MG list" <mgs@Autox.Team.Net>
Subject: Re: Fried wiring
From: "Paul Hunt" <>
Date: Mon, 25 Oct 2004 15:36:07 +0100
When you say the starter wasn't engaging do you mean that when you turned
the key to crank there was no whirring, no clunking or clicking or anything?
If you got any of those then that problem almost certainly isn't connected
to the fried wiring, if so it could well be.  But a faulty starter motor or
solenoid, even if it were shorting out, would not cause heat damage to
wiring at the steering column.

With the key off there should be voltage on the brown wires at the
alternator and the fusebox.  With the ignition on it should be at the
brown/yellow at the alternator and the white/brown at the fusebox as well.
On the brown/yellow but not the white/brown indicates a bad ignition relay
or connections to/from it.  On neither would indicate a bad ignition switch
or connections to/from it.  As well as an open-circuit causing these
problems a short-circuit can as well, and cause your fried loom into the
bargain.  If the only smoking wiring was that brown you mentioned and in the
cowl, not any other coloured wires in the column looms, then the problem
would seem to be in the cowl.  It's possible that a wire has been working
loose, possibly to or from the ignition switch, which has been causing the
failure to crank, then it came free altogether.  And if it was only the
removal of the battery cable that stopped the smoking, i.e. the ignition was
off at the time, then it will be a brown or a component it is connected to
i.e. the ignition switch that will be shorting out.

The main loom has a brown wire between the multi-plugs for the main lighting
switch and the ignition switch which could well be the wire you mention.  On
my schematic it goes to the main lighting switch plug first and if this is
so in practice that plug will have two brown wires on it, the other only
one.  Whichever has just the one wire, i.e. the ignition switch on the
schematic, is going to be the cause of the problem.

Remember that very high currents enough to smoke the wiring will quite
likely damage switches and connectors it is passing through, possibly enough
to cause bad connections and voltage drops where there shouldn't be any even
when the original cause of the problem is found and fixed.  Also remember
that the main brown wire up from the solenoid to the main lighting switch
will have been carrying that very high current and may also have suffered
damage inside the loom.


----- Original Message -----
From: "MonteMorris" <>
To: "MG list" <mgs@Autox.Team.Net>
Sent: Sunday, October 24, 2004 3:06 PM
Subject: Fried wiring

>...> Where should I start? Could the starter have finally died and caused
> I'll check back this evening when I get home.

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