No Display Trouble Isolation | Agilent Technologies 54835A, 45A, 46A

Chapter 5: Troubleshooting

No Display Trouble Isolation

No Display Trouble Isolation

This trouble isolation procedure helps isolate a problem to the assembly level when there is no display on the flat-panel liquid crystal display screen.

ARemove the cabinet and install the fan safety shield.

1 Disconnect the power cord from the oscilloscope. Refer to chapter 6, “Replacing Assemblies,” for instructions on removing the cabinet. Use care in handling the instrument.

2Install the optional fan safety shield, Agilent Technologies P/N 54801-00601, over the fans on the left side of the instrument.

WARNING		SHOCK HAZARD!
		The backlight inverter assembly, which is mounted at the front corner of the instrument near
		the flat-panel display, operates at 900 V at turn on. DO NOT handle this assembly while it is in
		operation.


WARNING		INJURY CAN RESULT!
		Once the cover is removed, the fan blades are exposed both inside and outside the chassis.
		Disconnect the power cable before working around the fan. Use extreme caution in working with
		the instrument when the cover is removed. Install the fan safety shield (Agilent Technologies
		P/N 54801-00601) on the side of the chassis over the fan. Failure to observe these precautions
		may result in injury.
		3 Connect the power cord and press the power switch on the front panel.

	B Check the fan connections.
		Verify that the fan mounted in the left side of the instrument and the CPU fan (on the
		motherboard) are connected.
		1 The instrument fans connect to the side of the Acquisition assembly at J3 and J5.
		2 The CPU fan connects to the top side of the motherboard at J46 (Fan Power).
		3 Connect the power cord and press the power switch on the front panel. Verify that both
		fans are running and that the front panel power switch LED is illuminated. These are
		indications that the power supply is functioning. If the fans and LED are off, go to the
		Power Supply Trouble Isolation flowchart.
	C Connect an external monitor, cycle power, and observe the instrument power-on
		sequence.
		See table 5-1 to check the visual and audible power-on sequence, and repair as needed, referring
		to other procedures as directed.

5–9

Image 86

Agilent Technologies 54835A No Display Trouble Isolation, Remove the cabinet and install the fan safety shield, Sequence

Contents

Agilent Model 54835A/45A/46A Oscilloscopes Ease of use with high performance Trigger setup controls set mode and basic parametersService Policy Display shows waveforms and graphical user interface Power Measurements This Book Contents To check the keyboard To check the LEDs ContentsNo Display Trouble Isolation To remove and replace the backlight inverter board Replaceable Parts To remove and replace the floppy disk drive General Information Model Description Instruments covered by this service guideOscilloscopes Covered by this Service Guide Accessories supplied Accessories supplied Option Number Description Options availableOptions available Required when using 2 or more Agilent 1144A active probes Accessories availableAccessories available Agilent 1144A MHz Active Probe Agilent Acquisition Specifications & characteristicsSpecifications & characteristics Specifications & characteristics Vertical Whichever is larger HorizontalOffset Accuracy Post-trigger Specifications & characteristics Trigger Specifications & characteristics Display Measurements Computer System/ Storage Rise Time figures are calculated from tr=.35/Bandwidth CAT I and CAT II DefinitionsVideo Output General Characteristics Agilent Technologies 54835A/45A/46A general characteristicsAgilent Technologies 54835A/45A/46A general characteristics Agilent Technologies 54835A/45A/46A general characteristics Recommended test equipment Agilent Service software No substitutionRecommended test equipment Agilent EPM Sensor 441A/Agilent 8482A Preparing for Use Preparing for Use To inspect the instrument To inspect the instrument Three-wire Power Cable is Provided To connect powerTo connect power To connect the mouse or other pointing device To connect the mouse or other pointing deviceTo attach the optional trackball To attach the optional trackball To connect the keyboard To connect the keyboardTo connect to the LAN card To connect oscilloscope probes To connect oscilloscope probes To connect a printer To connect a printer To connect an external monitor To connect an external monitorTo connect the Gpib cable To tilt the oscilloscope upward for easier viewing To tilt the oscilloscope upward for easier viewing You Can Configure the Backlight Saver To power on the oscilloscopeTo power on the oscilloscope To verify basic oscilloscope operation Press the Default Setup key on the front panelGraphical Interface Enable Button Press the Autoscale key on the front panel To clean the instrument To clean the instrumentTo clean the display monitor contrast filter Testing Performance Test Interval Dependencies See Also Averaging Let the Instrument Warm Up Before TestingClear Display To test the dc calibrator Enable the graphical interfaceProcedure Connect the multimeter to the front panel Aux Out BNC Selecting DC in the Calibration Dialog If the test failsSet Aux Output to DC Set the output voltage To test input resistance Input Resistance Equipment SetupTo test input resistance 25% accuracy Cables Connect the equipment SpecificationTo test voltage measurement accuracy To test voltage measurement accuracy Use the following table for steps 8 through Voltage Measurement Accuracy Equipment SetupAcquisition Setup for Voltage Accuracy Measurement Source Selection for Vavg Measurement Scale Offset Supply Tolerance LimitsSelect Channel 1 as the source for the Vavg measurement To Set Vertical Scale and Position Set the scale from the table Set the offset from the table To test offset accuracy To test offset accuracyUse the following table for steps 6 through Volts/div Position Supply Tolerance Limits To test offset accuracy Real Time Specification Equivalent TimeTo test bandwidth Equivalent Time Test Displayed. Note the Vamptd1 reading Calculate the response using the formulaSelect Vamptd from the Voltage submenu of the Measure menu Real Time Test MΩ, 500 MHz Test on 54835A, 54845A, and 54846A To test time measurement accuracy Equivalent Time Mode ProcedureTo test time measurement accuracy Equivalent Time ≥16 averages Horizontal Setup for Equivalent Time Procedure Waveform for Time Measurement Accuracy Check Acquisition Setup for Equivalent Time Procedure Source Selection for Delta Time Measurement Measurement Settings for Time Interval Measurement For valid statistical data New Measurement Settings for Delta Time Measurement Real-Time Mode Procedure Measurement Definitions for Real Mode Procedure Click Close Set horizontal time/div to 5 ns/div Acquisition Setup for Trigger Sensitivity TestTo test trigger sensitivity To test trigger sensitivity Setting the Markers for a 0.5 Division Reference Turn on Channel 1 and turn off all other channels Procedure-Auxiliary Trigger Test If a test failsPage Amplitude Input Channel Chan 4/Ext Resistance Agilent Technologies 54835A/45A/46A OscilloscopeTest Limits Results Vmax Vmin/5 = Voltage Scale Coupling Supply Limits Channel Channel 2 GSa/s Realtime Channel 4 GSa/sChannel 8 GSa/s ∆Time edge#101 Limits Calibrating and Adjusting Calibrating and Adjusting Let the Oscilloscope Warm Up Before Adjusting Loading New Software To check the power supply To check the power supplyDisconnect the oscilloscope power cord and remove the cover Equipment Critical Specifications Recommended Model/Part Power Supply Voltage Limits Supply Voltage Specification Limits Equipment Required To check the flat panel display FPD Flat-Panel Display SpecificationsWhen to Use this Procedure To check the flat panel display FPD Click Start Starting the Screen Test Repeat steps 6 and 7 for all colors Screen Test Self calibration To run the self calibrationTo run the self calibration Calibration time If calibration fails Click Start, then follow the instructions on the screenClear Cal Memory Protect to Run self calibration Click here to start calibrationPage Troubleshooting Troubleshooting To install the fan safety shield To install the fan safety shieldDisconnect the instrument power cord and remove the cover Installing the Fan Safety Shield To troubleshoot the instrument To troubleshoot the instrument Primary Trouble Isolation Flowchart Primary Trouble Isolation Primary Trouble Isolation Perform power-upPower-on Display Default Graphical Interface Disabled Check the display Run the Knob and Key selftest and the LED selftest Run oscilloscope self-testsCheck the front panel No Display Trouble Isolation Flowchart Check the fan connections Remove the cabinet and install the fan safety shieldNo Display Trouble Isolation Sequence Completed its power-on test LEDs do not come on, Power-onPower supply indicator Isolation flowchart Configure the motherboard Not, the problem may be with Power to the instrument.Solenoids are preset Normal operating pattern Board video signals Power Supply Trouble Isolation Flowchart Power Supply Trouble Isolation Power Supply Trouble IsolationCheck the power supply voltages Approximate Resistance Values, Each Power Supply to Ground Power Supply Distribution Replace any shorted assemblyOverride the Remote Inhibit signal Power-up Sense Resistor Connection Check +15 V Bias and Remote Inhibit cabling Replace the power supplyRouting of +15 V Bias and Remote Inhibit Signals Check for the oscilloscope display onscreen Pin Supply +3V Offset Data Probe ID Ring Clk +12 To check probe power outputsTo check probe power outputs To check the keyboard When you are finished, click CloseTest Procedure To check the keyboard Troubleshooting Procedure Re-assemble the instrument Test by Rows To check the LEDsTo check the LEDs LED Test Screen When you are finished, click Close Messages Vary Slightly To check the motherboard, CPU, and RAMTo check the motherboard, CPU, and RAM Signal To check the Svga display board video signalsTo check the Svga display board video signals Video Signals Backlight Inverter Board Input Voltages Input Pin # To check the backlight inverter voltagesTo check the backlight inverter voltages Backlight OFF Backlight on Post Code Listing Post Code Listing AMI Motherboard onlyPost Code Listing AMI Motherboard only Checkpoint Code Description Color settings next Keyboard BAT command is issuedUnblocking command Next Display memory read/write test next Clearing the memory below 1 MB for the soft reset next2Eh 2Fh Winbios Setup next Keyboard reset command nextCommand next After Winbios Setup next 9Ch 9BhCoprocessor text next 9Dh Motherboard / floppy drive configurations Bios setup To configure the motherboard jumpers and set up the BiosTo configure the motherboard jumpers and set up the Bios To configure the motherboard jumpers and set up the Bios Agilent Technologies Service Note Describes Upgrade Details To configure the motherboard jumpers and set up the Bios J37, J39 Configuring the AMI Series 727 Motherboard JumpersJ46 Series 727 Motherboard Jumpers J25J24 J37 MHz Clock Is RequiredJ2J21 J11 J12 Press F1 to run the Winbios setup To configure the AMI Series 727 Winbios Parameters System Keyboard Absent Do the following within the setup programWinbios Keyboard Commands Do steps h-l only if Your System has 64 Mb RAM Load Optimal Defaults Exit the Setup program, saving the changes you madeConfiguration Item Setting Primary Configuring the AMI Series 757 Motherboard for 200 MHz CPU Series 757 Rev C Motherboard Jumpers Pin Do not Press F2 When to Do this Procedure Series 757 System Bios Settings with 1.44 Mbyte floppy drive Configuring the AMI Series 757 Motherboard for 300 MHz CPU Series 757 Rev D Motherboard Jumpers J14 J16 AMI Atlas-III PCI/ISA Do the following within the setup program Series 757 System Bios Settings with 120 Mbyte floppy drive Off FIC VA-503A MotherboardCore S1-1 S1-2 S1-3 S1-4 Ratio S2-1 S2-2 Under the Power Management Setup, change these settings Under the PnP/PCI Configuration, change these settings To troubleshoot the acquisition system Under Integrated Peripherals, change these settingsIsolating Acquisition Problems To troubleshoot the acquisition system Acquisition Trouble Isolation 1 Acquisition Trouble Isolation 2 Acquisition Trouble Isolation 3 Acquisition Trouble Isolation 4 To D Converter FailedReturn the Known Good Attenuator to Original Channel Probe Board failed Temperature Sense failedFiso failed Offset DAC failed Interpolator failed Scroll Mode Counter failedTimer failed Timebase failed Attenuator Click Test To troubleshoot attenuator failuresTo troubleshoot attenuator failures Attenuator Connectivity Test Repeat steps 1 through 3 for the remaining input channelsSwapping Attenuators Attenuator Assembly Troubleshooting Select About Infiniium... from the Help Menu Enable the Graphical InterfaceSoftware Revisions Software RevisionsPage Replacing Assemblies Replacing Assemblies Remove all accessories from the instrument To return the instrument to Agilent Technologies for service Cover Fasteners To remove and replace the coverTo remove and replace the cover To disconnect the cable To disconnect and connect Mylar flex cablesTo disconnect and connect Mylar flex cables To reconnect the cable To remove and replace the AutoProbe assembly To remove and replace the AutoProbe assemblyDisconnect the power cable and remove the cover Disconnecting W13 Avoid Damage to the Ribbon Cable and Faceplate Pushing Out the AutoProbe Faceplate Removing the Probe Power and Control Assembly To remove and replace the probe power and control assemblyTo remove and replace the probe power and control assembly Avoid Interference with the Fan To remove and replace the backlight inverter board To remove and replace the front panel assemblyTo remove and replace the backlight inverter board Removing the Backlight Inverter Board Removing the BNC Nuts To remove and replace the front panel assemblySMB Cable W18 and Comp Wire W19 Disconnecting W16, W20, and the Backlight Cables Front Panel Side Screws Keep Long Screws Separate for Re-assembly Front Panel Cover Plate Screws Removing the Cursor Keyboard Removing the backlights Removing the Acquisition Assembly To remove and replace the acquisition board assemblyTo remove and replace the acquisition board assembly To remove and replace the LAN interface board To replace the board, reverse the removal procedureTo remove and replace the LAN interface board Removing the LAN Interface Board Removing the Gpib Interface Board To remove and replace the Gpib interface boardTo remove and replace the Gpib interface board Disconnect these cables from the Svga display board Removing the Scope Interface and Svga Display Boards To separate the scope interface board and Svga display board To separate the scope interface board and Svga display board To remove and replace the Option 200 sound card To replace the card, reverse the removal procedureTo remove and replace the Option 200 sound card Removing the Hard Disk Drive To remove and replace the hard disk driveTo remove and replace the hard disk drive To remove and replace the floppy disk drive To remove and replace the floppy disk driveTo remove and replace the motherboard Removing the Floppy Disk Drive Screws Removing the Motherboard Torx Screws Disconnect these cables from the motherboardTo remove and replace the motherboard To remove and replace the motherboard Removing Power Supply Cables To remove and replace the power supplyTo remove and replace the power supply To remove and replace the fan To install the fan, reverse this procedureTo remove and replace the fan Removing Fan Fasteners Removing the CPU To remove and replace the CPUTo remove and replace the CPU Removing and replacing SIMMs on the AMI motherboard To remove and replace RAM SIMMs or Sdram DIMMsTo remove and replace RAM SIMMs or Sdram DIMMs Removing RAM SIMMs Do Not Remove the Attenuators from the Acquisition Board To remove and replace an attenuatorTo remove and replace an attenuator If You Permanently Replace Parts Removing an Attenuator Self Test To reset the attenuator contact counterTo reset the attenuator contact counter Repeat for each channel you need to change Attenuator Relay Actuations SetupAttenuator Channel box, select the channel you are changing To remove the acquisition hybrid To remove and replace an acquisition hybridTo remove and replace an acquisition hybrid To replace the acquisition hybrid Do not USE Excessive Force Hybrid Connector Removing the Hybrid Connector Replaceable Parts Unlisted Parts Ordering Replaceable PartsListed Parts Direct Mail Order System Plug Type Cable Plug Description Length Color Country In/cm Power Cables and Plug ConfigurationsPower Cables and Plug Configurations MP61 MP17 MP62 or MP63 MP15 and MP49 Exploded ViewsExploded Views Front Frame and Front Panel Fan and Acquisition Assembly H12 H24 H25 MP55 MP60 H11 Power Supply and PC MotherboardA10 MP57 Exploded Views A4A1W24/25 A4A4 Exploded Views Exploded Views H23 A4A2 FIC VA-503A Motherboard for PC Motherboard ConfigurationW17W20 A15 W14 W11 A19 W16 A14 W24/25 W27 W22 A4A1 Exploded Views MP12 Sleeve and Accessory PouchMP14 MP52 MP70 MP72 H10 MP20 MP13 H19 H26 MP19 Attenuator Assembly Replaceable Parts List Replaceable Parts List Agilent Part Des Number QTY DRAM-SIMM 2MX32 8 MB Simm DRAM-DIMM 16MX32 64 MB Dimm Fans Cables Display BD. Jumper Page Theory of Operation Theory of Operation Block-Level Theory Power Supply AssemblyFPD Monitor Assembly Disk Drives Acquisition SystemFront Panel Attenuators Gpib Interface Card Probe Power and ControlSvga Display Card Acquisition Block Diagram Attenuator Theory Attenuator TheoryAcquisition Theory Acquisition Board Acquisition Theory Acquisition Modes Scope Interface BoardPage Supplementary Information Manufacturer’s NameManufacturer’s Address Product Regulations Restricted Rights Legend Product Warranty