IBM 5150 Hardware Maintenance Manual page 243

Left Margin Adjustment (continued)
12.
Set your multimeter to the 12 V dc scale.
13.
Place the negative (-) lead of the meter on the ground pin of the
driver circuit card.
~
14.
Place the positive (+) lead of the meter on the yellow wire
solder connection on the left margin sensor.
Negative (-) Lead to Ground
Driver Circuit Card
Pin on DriverCircuit Card
Left
Frame
Positive (+) Lead to
Yellow Wire Connection
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