Short Circuit sinking in excess of 35A blows fuse when all protected
circuits are not faulty

SYMPTOMS
Fuse 1 (35A) intermittently blowing in use. The same fuse later constantly
blows as soon as the ignition key is turned to position II, just when the
vehicle's operator is on their way to work.

Fuse 1 protects the following components:
Brake Lights
Indicators
Rear Windscreen Demister
Reversing Lights

All connections appear sound. Disconnecting all protected circuits fails to
identify the source of the problem.

CAUSE
Two wires feed and return current to the Reversing Light switch fitted to
the gearstick housing. These wires pass through a substantial and complete
wiring grommet from inside and are cable-tied to the steady bar.

Although these wires and the bullet connectors therein are mostly protected
from the elements by the copious amounts of underseal, grease and general
oil leak spray from the differential housing/rod oil seal, vibration and
surface rust on the steady bar lead to the chafing of the insulation of one
or both wires. This creates a short circuit which gives the symptoms
described above.

RESOLUTION
Allow at least 30 minutes for the replacement of chafed wiring and another 2
days for unforseen problems such as:
lack of bullet connectors
lack of tools/facilities including wheel ramps and/or axle stands
weather conditions

Remove the cable tie and scrape the excess oil/grease/underseal from the
bullet connectors. Holding each half of the join lightly but firmly with
pliers, separate the connection. The pliers are necessary to avoid
half-frozen hands slipping on the oil/grease residue and frustrating the
operator to the point that they say "sod it" and return inside for a beer.

Working inside the car, lift the carpets to provide access to the floor in
front of the gearstick gaiter. The water typically discovered beneath the
carpet is the subject of another MOKB article. Locate the grommet and the
two wires running therein. Pull the grommet and the wires through and
inspect them for chafing/damage. Expect to find a small nick or wear on one
of the wires but do not be surprised if you find 1/2" or more of
spark-oxidised and exposed wire on each.

Cut out all exposed wires, plus a small amount to give access to clean,
untarnished, unoiled, unundersealed, ungreased wire. Replace the wire with
either crimp-type bullet connectors or butt connectors and waterproof with
heatshrink sleeving and copious amounts of PVC tape. Take care to apply
sufficient tape to waterproof and protect the joins but do not apply so much
that the two wires will not pass through the grommet.

Pass the wires back through the floor taking care to replace the grommet in
its correct position.

Working outside the car, in the pi55ing rain on a soaking wet driveway with
the rain pounding down, route the wires to prevent fouling and rejoin the
bullet connections. Smear some of the oil/grease to hand in that area around
the join in the bullet connectors; this may help to protect against water
ingress at a later date, but no guarantees or warranties express or impiled
are given.

Rest the two wires in their original position on the steady bar and apply
two small cable ties to hold the wires in place. The aid of pliers may be
advantageous to grip and tighten the cable ties.

Replace Fuse 1 and test.

STATUS
Miniowner has confirmed this to be a problem in the design of the Reverse
Light switch cable run and suggests that other operators of such vehicles
carry out the resolution detailed above as a preventative measure. The loss
of Fuse 1 can lead to seriously reduced visibility through the rear
windscreen. It is also worth mentioning that other road users will be
unaware of your intent to reverse, turn or stop.

Added 16 Dec 2002