HP Color LaserJet Pro M154

A blank control panel display can be caused by one or more of the following:

• No power to the printer.
• Power supply has tripped (over-current/over-voltage/temperature issue).
• Formatter not fully seated.
• Faulty component installed on the formatter (for example a WiFi PCA).
• Control panel connector not fully seated.
• Faulty formatter.
• Faulty DC controller (on the engine controller unit).
• Faulty control panel.

Troubleshooting a blank control panel

1. Verify that power is available to the printer. If the printer is plugged into a surge protector or uninterruptible power supply (UPS), remove it, and then plug the printer directly into a known operating wall receptacle (make sure that the wall receptacle provides the correct voltage and current for the printer).
2. Make sure that the power switch is in the on position.
3. Make sure that the fan runs briefly, which indicates that the power supply is operational.
4. Make sure that the control-panel display wire harness is connected.
5. Make sure that the formatter is seated and operating correctly. Turn off the printer and remove the formatter. Reinstall the formatter, make sure the power switch is in the on position, and then verify that the network LED (amber) is blinking and that the link LED (green) is illuminated.
6. Remove any external solutions, and then try to turn the printer on again.
7. If the control panel display is blank, but the main cooling fan runs briefly after the printer power is turned on, try printing an engine-test page to determine whether the problem is with the control-panel display, formatter, or other printer assemblies.
   With the printer on and in the Ready state, open and then close the front door four times (for a simplex print out on both simplex and duplex models) or five times (for a duplex print on duplex models). The printer will print the engine test page.
   If the engine test page prints, the print engine is operating normally (a failed engine test print page does not necessarily indicate that the print engine or DC controller is defective).
   Use the control-panel diagnostics to test the control panel. See the Control panel checks section below. If the error persists, proceed to the next step.
8. If the print engine appears to be correctly operating (the engine test page successfully printed) and the control panel is still blank, replace the low-voltage power supply (LVPS).
9. If after replacing the LVPS normal startup noises and lights are still not present, replace the DC controller.
   NOTE: If the error persists after replacing these assemblies, escalate the problem to the Global Business Unit (GBU).