Phaser 5400 Laser Printer Service Guide 151RAP 58 Toner Sensor Assembly.Table 88 Toner Sensor Assembly Troubleshooting ProcedureStep Actions and Questions Yes No1 PROCEDURE1. Switch printer power OFF.2. Remove the Left Side Cover [RRP 1.1, page 250] andthe Print Engine Controller Board Cover [RRP 8.5,page 310].3. Open the Top Cover and remove the Print Cartridge.4. Cheat the Top Cover Interlock.5. Disconnect P/J14 from the Print Engine ControllerBoard.6. Switch printer power ON.7. Measure the voltage between P14-1 on the PrintEngine Controller Board and frame ground.Does the voltage measure +2.0 VDC?Go toStep 3.Go toStep 2.2 ìNOî FROM STEP 1 ABOVEMeasure the voltage between P/J16-9 on the PrintEngine Controller Board and frame ground.Does the voltage measure + 24.0 VDC?Replace thePrint EngineControllerBoard[RRP 8.5,page 310].Replace theLVPS[RRP 8.6,page 312].3 ìYESî FROM STEP 1 ABOVEMeasure the voltage between P14-3 and frame ground.Does the voltage measure +5.0 VDC?Go toStep 4.Replace thePrint EngineControllerBoard[RRP 8.5,page 310].4 ìYESî FROM STEP 3 ABOVE1. Switch printer power OFF.2. Reconnect P/J14.3. Switch printer power ON.4. Raise and lower the Print Cartridge approximately 2inches (50.8 mm) while measuring the voltagebetween P/J14-3 and frame ground.Does the voltage measure +5.0 VDC when thecartridge is in place and 0.0 VDC when thecartridge is raised?Problemsolved.Go toStep 5.5 TONER SENSOR HARNESS CONTINUITYCHECK1. Switch printer power OFF.2. Disconnect P/J14 from the Print Engine ControllerBoard and P/J 141 from the Toner Sensor.3. Check for continuity between all pins of P/J14 andP/J141.Is there continuity between all the pins tested?Replace theTonerSensorAssembly[RRP 7.3,page 301].Repair orreplace theTonerSensorHarness[PL 8.1,page 402],asnecessary.
