User`s guide

Flowcharts and TablesTroubleshooting
Table 3. Toner LED Is On or Flashes After Printer Warmup
Step Check Result Action
1 Try a known-good toner
cartridge. Does the
problem persist?
No Problem solved.
2 Have you recently ser-
viced the printer and has
this symptom existed
ever since?
Yes You probably did not fully reseat the
high-voltage power supply, connector
block, or transfer block assembly; or
connector J210 on the DC Controller
board is not secure. Make sure these
modules are securely installed.
3 Have you just performed
the engine diagnostic?
Yes Confirm there is not still a serial loop-
back connector installed in the serial
port.
4 Remove the toner car-
tridge and inspect all the
toner contacts for damage
or excess toner buildup.
Are the contacts clean
and in good condition?
No Clean or repair the contacts if possi-
ble. Take special note of TB403, which
is the pronged contact that the toner
cartridge mates into. This contact ties
into the toner sensor inside the car-
tridge.
5 Remove the rear panel
and I/O shield. Place
probes between J210-6
(HVRST) and J210-10
(GND) and switch on the
printer. Does the voltage
change from 0 to 5 V
about one second after
the printer starts up?
No
Ye s
Replace the DC Controller board.
Perform the first module exchange
below. If the problem persists, reinstall
the original module and perform the
next exchange:
• Replace the HV power supply
• Replace the power supply-to-
HVPS interface board.
• Replace the transfer block assembly.
• Replace the DC controller-board-to-
HVPS cable.