Power Transistor (Ignition Module)

NOTE: When testing the power transistor(s), an analog-type circuit tester should be used.

To test the No. 1 and 4 cylinders:
1. Select the ohm range on the analog tester and connect the tester between terminals 1 and 3.
  
  Fig. 1: Terminal identification of the power transistor
2. Connect the positive (+) lead of a 1.5 volt dry cell battery between terminal 2 and the negative lead to terminal 3.
3. Continuity should be indicated when the dry cell is connected. No continuity should be indicated when the dry cell is disconnected.
To test the No. 2 and 3 cylinders:
1. Select the ohm range on the analog tester and connect the tester between terminals 6 and 3.
2. Connect a 1.5 volt dry cell battery between terminals 3 and 5. The positive (+) lead connects to terminal 5 and the negative (-) to terminal 3.
3. Continuity should be indicated when the dry cell is connected. No continuity should be indicated when the dry cell is disconnected.
If the results of the tests are not as indicated above, replace the power transistor.

To test the No. 1 and 4 cylinders:
1. Connect the negative terminal of a 1.5 volt dry cell battery to terminal 3 of the power transistor; then check whether there is continuity between terminals 7 and 3 when terminal 6 and the positive (+) terminal are connected and disconnected.
  NOTE: Connect the negative probe of the tester to terminal 7 of the power transistor.
  
  Fig. 2: Testing No. 1-No. 4 coil side of the power transistor
2. With terminal 6 and the positive (+) lead connected, there should be continuity between terminal 7 and terminal 3. With terminal 6 and the positive (+) lead disconnected, there should be no continuity between terminal 7 and terminal 3.
To test the No. 2 and 3 cylinders:
1. Connect the negative terminal of a 1.5 volts dry cell to terminal 3 of the power transistor; then check whether there is continuity between terminals 1 and 3 when terminal 2 and the positive (+) terminal are connected and disconnected.
  NOTE: Connect the negative probe of the tester to terminal 1 of the power transistor.
  
  Fig. 3: Testing No. 2-No. 3 coil side of the power transistor
2. With terminal 2 and the positive (+) lead connected, there should be continuity between terminal 1 and terminal 3. With terminal 2 and the positive (+) lead disconnected, there should be no continuity between terminal 1 and terminal 3.
If the results of the tests are not as indicated above, replace the power transistor.

To test the No. 1 and 4 cylinders:
1. Connect the negative terminal of a 1.5 volt dry cell battery to terminal 3 of the power transistor; then check whether there is continuity between terminals 8 and 3 when terminal 7 and the positive (+) terminal are connected and disconnected.
  NOTE: Connect the negative probe of the tester to terminal 8 of the power transistor.
2. With terminal 7 and the positive (+) lead connected, there should be continuity between terminal 8 and terminal 3. With terminal 7 and the positive (+) lead disconnected, there should be no continuity between terminal 8 and terminal 3.
To test the No. 2 and 3 cylinders:
1. Connect the negative terminal of a 1.5 volt dry cell battery to terminal 3 of the power transistor; then check whether there is continuity between terminals 1 and 3 when terminal 2 and the positive (+) terminal are connected and disconnected.
  NOTE: Connect the negative probe of the tester to terminal 1 of the power transistor.
2. With terminal 2 and the positive (+) lead connected, there should be continuity between terminal 1 and terminal 3. With terminal 2 and the positive (+) lead disconnected, there should be no continuity between terminal 1 and terminal 3.
  
  Fig. 4: Testing the power transistor for cylinders No. 1 and 4
  
  Fig. 5: Testing the power transistor for cylinders No. 2 and 3
If the results of the tests are not as indicated above, replace the power transistor.