Troubleshooting
274 372 SPU 780 01EMAN May 2002
Manual Procedure List

Procedure One Controller failed to power up with good AC supply and fuse OK:

Procedure Two To replace a 38x/48x fuse:

Procedure Two To replace a 68x/78x fuse:

Step Action
1 Ensure that the power supply jumper is correct on the slot mount controllers.
2 Check the input power select switch position is correct for supply voltage.
3 Check for loose crimps or screws at the power supply terminal strip.
4 Check fuses where relevant.
Step Action
1 Remove memory and executing cartridges.
2 Remove 9 screws that hold the side (1/4 inch nut driver).
3 Remove line cord cover screws and the plastic line cord cover.
4 Remove 2 line cord standoffs (3/16 inch nut driver).
5 Remove screws near battery compartment.
6 The front part of the controller can now separate from the circuit board. The fuse
is located near the AC power connector.
7 Replace fuse with the same size and type.
Step Action
1 Remove 2 thumbscrews and 2 machine screws with start washers as shown on
front view.
2 Remove small cover.
3 Remove 4 machine screws from rear cover and slide rear cover back 3 inches.
(Exec pack cover may have to be removed from the right side).
4 Carefully slide the left side section toward the back expose the two fuses.
5 Replace blown fuses with the same type and size.