HP LaserJet II Serie Manual De Instrucciones página 240

HP 33440/HP 33449 COMBINED SERVICE MANUAL
Developer DC Bias Functional Check
Verify that the Developer DC Bias (DBDC) enable signal on the High-Voltige Power Supply
Assembly is functioning as follows:
1. Using a voltmeter and frame ground as a reference, measure the voltage level at J21O-4 (Test
Connector, see Figure 7-30) on the DC Controller PCA while initiating the printer SeH Test.
The voltage level should titch between +18.0 Vdc (disabled state) and 0.0 Vdc (enabled state)
one second after the print cycle begins. If the voltage at J21O-4 does not switch, replace the DC
Controller PCA. If the signal line is being switched but the developer DC bias does not appear
to be functioning (i.e., producing e=remely faint or white pages), replace the EP-S Cartridge
fo~owed by the High-Voltage Power Supply Assembly.
Figure
7-30. J21O
Test Points
—
—
Note
Functionality of the DC Controller's high-voltage control circuitry can be
~1
readily verified using the tiserJet Series II Sewice Diagnostic Tool Kit, P/N
w
33440-67905, and following the instructions therein.
7-76