Specifications

84A-20
CONTROL - SIGNALS
Heated rear screen: Repair
84A
The screen printed heated grid on the inner face of the
window may have an accidental cut, making the affect-
ed part of the circuit useless.
a Determine the exact location of the cut using a volt-
meter.
Faults such as these can be repaired by using the
heated rear screen varnish available at the. Maga-
sin Pièces de Rechange
I - DETERMINING THE EXACT LOCATION OF THE
CUT USING A VOLTMETER
a Switch on the ignition.
a Switch on the heated rear screen supply.
1 - Detection between lines B and A
a Connect the + wire of the voltmeter to the + feed ter-
minal of the rear screen.
a Put the - wire of the voltmeter on a filament at the -
terminal side of the rear screen (line B); the voltage
obtained should be roughly equal to that of the bat-
tery.
a Move the wire - to line A (arrowed line): the voltage
gradually drops.
a A sudden voltage drop indicates that the filament is
cut at that point (carry out this operation for each fil-
ament).
2 - Detection between lines C and A
a Connect the - wire of the voltmeter to the - terminal
of the rear screen.
a Put the + wire of the voltmeter on the filament at the
+ terminal end of the rear screen (line C); the voltage
obtained should be roughly equal to battery voltage.
a Move the + wire towards line A (arrowed line); the
voltage gradually drops.
a A sudden voltage drop indicates that the filament is
cut at that point (carry out this operation for each fil-
ament).
II - REPAIRING THE FILAMENT
a Clean the section to be treated to remove all dust or
grease, preferably using alcohol or a glass cleaner,
and wipe with a clean, dry cloth.
a To ensure that the new line is straight, before var-
nishing, apply adhesive tape to either side of the
section to be repaired, leaving the conducting line
exposed.
a Before using the varnish, shake the bottle to prevent
the silver particles settling at the bottom.
Repair
a Carry out the repair using a small brush, applying a
sufficiently thick layer. If applying successive coats,
allow sufficient drying time between each coat and
do not repeat the operation more than three times.
a If an error is made with the varnish (runs, smudges,
etc.), it can be removed using a knife point, but only
after several hours, once the product has properly
hardened.
8814
8815