MSD 7330 7AL-3 Ignition Control Installation - Manual (Page 10)

10 INSTALLATION INSTRUCTIONS
M S D
• W W W . M S D P E R F O R M A N C E . C O M • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • F A X ( 9 1 5 ) 8 5 7 - 3 3 4 4
KILL SWITCH
If your racing application requires an ignition kill switch it is easy to incorporate into the ignition's
trigger input wire. When the trigger input terminal is grounded, the ignition is killed. A Single-Pole,
Single Throw Switch is required (MSD PN 8806).
Points: Connect one side of the switch to ground and the other side to the Points terminal of 7AL-3
(Figure 17).
Mag Pickup: Connect one side of the switch to ground and the other side to the Mag+ terminal of
7AL-3 (Figure 18).
TROUBLESHOOTING
If for some reason you suspect that the ignition system is not functioning properly, follow the proceeding
procedures to determine if the MSD is functioning properly.
TRIGGER LED
The MSD 7AL-3 is equipped with a Green LED..
Green: The Green LED indicates that the ignition is receiving a trigger signal. If it is not operating, the
trigger mechanism, either crank trigger or distributor, is not delivering a trigger signal. If the engine
will not run though the Green LED shows a trigger signal, follow the "Checking for Spark" procedure
on page 11.
MSD offers an Ignition Tester, PN 8998, that will check the Ignition and Coil's operation.(The obsoleted
Tester PN 8995, can only be used on the points input.)
RAS
ON/OFF
Figure 17 Connecting a Kill Switch to Points.
RAS
ON/OFF
Figure 18 Connecting the Kill Switch to the Mag+.
Figure 16 Connecting a Tachometer.
RAS
ON/OFF
TACHOMETER
This terminal provides a square wave 12 volt, 20% duty
cycle signal for your tachometer. Use the supplied Brown
wire and connect it to the Tach terminal strip (Figure 16). If
your tachometer reads erratic or does not operate properly,
a Tach Adaptor may be required. If you are using the white
wire to trigger (points input) you will need Adapter PN 8910.
If you are using the magnetic pickup, PN 8920 will be the
right Adapter. Contact your MSD dealer.