1. Check for continuity between pins 4 and 6 (switch) on P2.
2. If the switch is OK, short pin 4 to pin 6 on P2 and check the power supply voltages.

    _________________ __________________ _________________ _________________  
   | -Lead Pin       | +Lead Pin        | V dc Minimum    | V dc Maximum    | 
   |_________________|__________________|_________________|_________________| 
   | 4               | 1                | +3.75           | +6.25           | 
   |_________________|__________________|_________________|_________________| 

    _________________ __________________ _________________ _________________  
   | -Lead Pin       | +Lead Pin        | V dc Minimum    | V dc Maximum    | 
   |_________________|__________________|_________________|_________________| 
   | 6               | 1                | + 9.0           | +15.0           | 
   |_________________|__________________|_________________|_________________| 
   | 3               | Power Good       |                 |                 | 
   |_________________|__________________|_________________|_________________| 
   | 4               | On/Off Signal    |                 |                 | 
   |_________________|__________________|_________________|_________________| 
   | 6               | 5                | - 9.0           | - 15.0          | 
   |_________________|__________________|_________________|_________________| 
   | 6               | Ground           |                 |                 | 
   |_________________|__________________|_________________|_________________| 
   | 6               | 7                | -4.75           | - 5.5           | 
   |_________________|__________________|_________________|_________________| 

    _________________ __________________ _________________ _________________  
   | -Lead Pin       | +Lead Pin        | V dc Minimum    | V dc Maximum    | 
   |_________________|__________________|_________________|_________________| 
   | 2               | 1                | + 9.0           | +15.0           | 
   |_________________|__________________|_________________|_________________| 
   | 2, 3            | Ground           |                 |                 | 
   |_________________|__________________|_________________|_________________| 
   | 3               | 4                | +3.75           | +6.25           | 
   |_________________|__________________|_________________|_________________| 

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