3006 Guard interlock.
Sheet 5 Plug 3 Pin-b
a) Check that all the machine guards are closed and the 'Guard Reset' switch operated (if fitted). Press the 'Error' pushbutton to cancel the error. 

b) If the same error persists check for a 24 volt signals on TB-1 in the Power Distribution Panel:-
Wire nos. 500 (24 volt supply), 538 (if fitted, right hand magazine guard), 537 (left hand magazine guard), 536 (left hand spindle guards), 544 (right hand spindle guards) and 518 (safety relay if fitted). If 24 volts is not present at terminal 500, then check the indicator-fuse 3 in the PDP and replace if necessary. If 24 volts is not present at terminals 538, 537, 536 or 544, then the associated safety switch or wiring is at fault. If 24 volts is present at all but terminal 518, then the guard reset switch, SR relay or coil-protection diode on SR relay is at fault. If 24 volts is present at terminal 518, then press the 'Error' pushbutton to cancel.

c) If the same error code persists the fault may be in the wire 518 from TB1 to Plug 3, pin-b, or a faulty 'Digital Input Board', DI 500 or DI 502. Switch off the control and transpose the 'DI' boards situated in the lower rack to the left. Power-up the machine. If the fault disappears, or a different, unrelated error code shows-up, then the 'DI' board is faulty and a replacement is required. If the same error code persists switch off the machine, remove plug 3 and check the continuity from Plug 3, pin-b to terminal 518. There may be a spare wire in the cable loom to utilize if wire 518 appears to be broken.

d) If the wiring is O.K. the fault may be with the 'Watchdog' board (WD 50x) in the control or corruption of the memory. If another control is available the 'Watchdog' boards can be exchanged to test. If the memory is to be reloaded remember to punch-out programme and tool information first (although an up to date back-up tape should always be held).