HP LaserJet II Serie Manual De Instrucciones página 210

HP 33440/HP 33449 COMBINED SERVICE MANUAL
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"16 TONER LOW" Message
A toner sensing mechatism is lomted in the toner mvity of the EP-S Cartridge. The function
of this mechanism is similar to an antenna, sensing the AC developer bias voltages applied to
the developer tiure by the High-Voltage Power Supply Assembly. The output sensed by this
antenna is input back to the High-Voltige Power Supply (TSENS), where it is amplified and input
to the DC Controller to be compared agtinst a preset threshold value. If the toner level in the
catiridge falls below the minimum level and, consequently, the monitored voltage level falls below
the threshold level, the 16 TONER LOW message is displayed.
Table 7-18. "16 TONER
LOW" Checks
1. Is the EP-S Cartridge out of toner? Shake the EP-S Cartridge. If the message
persists, replace the cartridge.
2. Are the toner level sensor connectors Inspect connectors for damage (see FiWres 7-18
damaged?
and 7-19). If damaged, correct or replace.
3. Is the EP-S Cartridge defective? (See Figare Replace the EP-S Cartridge if visibly damaged.
7-19.)
4. Is the high-voltage connector cable, from the Visually inspect. Reseat or replace if necessary.
base of the printer (J601) to the DC Controller
PCA, fully seated or damaged?
5. Is the High-Voltage Power Supply Assembly See the "Toner Low Functional Check"
defective?
following this table.
6. Is the DC Controller PCA defective?
See the "Toner Low Functional Check"
following this table.
Toner Low Functional
Check
Since there is no good way to measure whether the toner low sensing system is malfunctioning
(i.e., the warning message is constantly being displayed or is never displayed), replace the following
components in the order listed:
1.
2.
3.
4.
EP-S Cartridge.
High-Voltage Power Supply Assembly.
High-Voltage Power Supply Cable (from the DC Controller).
DC Controller PCA.
7-46