Phaser 4500/4510 Service Manual 4-25
General Troubleshooting
5 V Interlock, Interlock Switch Assembly
Troubleshooting Reference
Applicable Parts Wiring and Plug/Jack Map References
■ 5 V Interlock
■ Interlock switch assembly
■ Laser unit harness assembly
■ LVPS harness assembly
■ LVPS
■ HVPS/engine logic board
■ “Laser Unit, 5 V Interlock, Interlock Switch
Assembly” on page 10-29
■ “Print Engine Wiring Diagrams” on page 10-19
■ “Print Engine Plug/Jack Locator” on page 10-3
Troubleshooting Procedure
Steps Actions and Questions Yes No
1 Check the 5 V Interlock:
1.Disconnect P/J142.
2.Test for continuity across P/J142-1 <=>
P/J142-2 while manually operating the
switch.
Is the switch continuous when pushed and
open when released?
Go to step 2. Replace the 5
V Interlock
(page 8-40).
2 Check the interlock switch assembly
1.Disconnect P/J144.
2.Test for continuity across P/J144-1 <=>
P/J144-2 while manually operating the
Laser Interlock.
Is the switch continuous when pushed and
open when released?
Go to step 3. Replace the
interlock
switch
assembly
(page 8-12).
3 Check the LVPS harness assembly
1.Disconnect P/J141, P/J142 and P/J144
of LVPS harness assembly.
2.Test for continuity across the following
points:
■ J141-2 <=> P142-1
■ J141-1 <=> P144-2
■ J142-2 <=> P144-1
Are all continuous?
Go to step 4. Replace the
LVPS harness
assembly.
4 Check the laser unit harness assembly:
1.Disconnect P/J141, P/J14 and P/J140 of
the laser unit harness assembly.
2.Test for continuity across the following
points:
■ P141-1 <=> J14-1
■ P141-2 <=> P140-8
Are both continuous?
Go to “LVPS
(Low Voltage
Power
Supply)” on
page 4-4.
Replace the
laser unit
harness
assembly.