LG DLP Projector Service Manual

CONTENTS

• SAFETY PRECAUTIONS
• SPECIFICATION
• SOFTWARE UPDATE
• BLOCK DIAGRAM
• EXPLODED VIEW
• DISASSEMBLY GUIDE
• ASSEMBLY GUIDE
• TROUBLE SHOOTING GUIDE

SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by [!] in the Exploded View. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer.

General Guidance

An isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC power line. Use a transformer of adequate power rating as this protects the technician from accidents resulting in personal injury from electrical shocks. It will also protect the receiver and its components from being damaged by accidental shorts of the circuitry that may be inadvertently introduced during the service operation.

If any fuse (or Fusible Resistor) in this PROJECTOR receiver is blown, replace it with the specified. When replacing a high wattage resistor (Oxide Metal Film Resistor, over 1 W), keep the resistor 10 mm away from PCB. Keep wires away from high voltage or high temperature parts.

Before returning the receiver to the customer

Always perform an AC leakage current check on the exposed metallic parts of the cabinet, such as antennas, terminals, etc., to be sure the set is safe to operate without damage of electrical shock.

Leakage Current Cold Check (Antenna Cold Check)

With the instrument AC plug removed from AC source, connect an electrical jumper across the two AC plug prongs. Place the AC switch in the on position, connect one lead of ohm-meter to the AC plug prongs tied together and touch other ohm-meter lead in turn to each exposed metallic parts such as antenna terminals, phone jacks, etc. If the exposed metallic part has a return path to the chassis, the measured resistance should be between 1 MΩ and 5.2 MΩ. When the exposed metal has no return path to the chassis the reading must be infinite. An other abnormality exists that must be corrected before the receiver is returned to the customer.

Leakage Current Hot Check (See below Figure)

Plug the AC cord directly into the AC outlet. Do not use a line Isolation Transformer during this check. Connect 1.5 KΩ / 10 watt resistor in parallel with a 0.15 µF capacitor between a known good earth ground (Water Pipe, Conduit, etc.) and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more sensitivity. Reverse plug the AC cord into the AC outlet and repeat AC voltage measurements for each exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which is corresponds to 0.5 mA. In case any measurement is out of the limits specified, there is possibility of shock hazard and the set must be checked and repaired before it is returned to the customer.

Leakage Current Hot Check circuit diagram: Depicts an AC Volt-meter connected across a 1.5 Kohm/10W resistor and a 0.15 uF capacitor, which are in turn connected between the instrument's exposed METALLIC PARTS and a Good Earth Ground (such as WATER PIPE, CONDUIT etc.).

SPECIFICATION

NOTE: Specifications and others are subject to change without notice for improvement.

1. Application range

This spec sheet is applied to all DLP Projectors with FZ91A chassis.

2. Requirement for Test

Each part is tested as below without special appointment:

• Temperature: 25 °C ± 5 °C, CST: 40 °C ± 2 °C
• Relative Humidity: 65 % ± 10%
• Power Voltage: Standard input voltage (100~240V @ 50/60Hz)
• Standard Voltage of each product is marked by models.
• Specification and performance of each part are followed by each drawing and specification by part number in accordance with BOM.
• The receiver must be operated for about 30 minutes prior to the adjustment.

3. Test method

• Performance: LGE PROJECTOR test method followed.
• Required other specification:
• Safety: KCC, IEC, CE specification (EN55022 Class B), CCC.
• EMC: KCC, IEC, CE specification (EN60950-1), CCC.
• Wireless: WIFI module, Bluetooth module - Korea, NA.

4. Model General Specification

5. Supported video resolutions

5.1. HDMI Input (PC/DTV)

SOFTWARE UPDATE

Follow these steps to update the projector's firmware:

1. Turn on the Projector.
2. Insert the USB drive containing the firmware. The firmware must be copied to the "LG_DTV" folder on the USB drive.
3. When the USB is inserted into the Projector, the USB UPDATE window will be displayed automatically.
4. Select the [INSTALL] button. The [USB UPDATE IN PROGRESS] window will be displayed, and the update will begin.
5. Select the [Check Now] button to check the update progress.
6. When the update progress is completed, [NEW UPDATE INSTALLED] will be displayed. Select the [YES] button to restart the Projector.
7. If a Content list is displayed (similar to Picture 5), select the [x] button to continue the update process.

If the Projector is connected to the Internet via Wired or Wireless AP, it will update automatically.

BLOCK DIAGRAM

The block diagram illustrates the internal components and their interconnections:

• MAIN IC100: The central processing unit, receiving signals from various inputs like HDMI/ARC, USB2.0, and SPDIF OUT. It interfaces with other modules via LVDS, SPI, and I2C buses.
• KEYSTONE IC800: Handles keystone correction functionality.
• MICOM IC600: Microcontroller unit, managing various functions, including keypad input and IR signals. It uses X-tal for timing.
• Panel(S) IC1010 & Panel(M) IC1000: Drive the projector's display panel, communicating via TTL and I2C.
• PMIC IC1004: Power Management IC, regulating power distribution.
• Wheel Driver IC1009: Controls the color wheel motor.
• LD Driver IC1300: Drives the laser diodes (LD 1-8) for the light source.
• Audio AMP IC700: Amplifies audio signals for the speakers (SPK).
• Other Components: EEPROM, eMMC, WIFI & Bluetooth Combo, Serial Flash, Oscillators, ACCELEROMETER, KEYPAD, IR receiver, DMD (Digital Micromirror Device), Phosphor Wheel, and Laser Diodes (LD).
• Input/Output Ports: HDMI/ARC, USB2.0 (Type-A), SPDIF OUT, RJ45 Jack, Headphone, Tuner, DC_IN.

EXPLODED VIEW

The exploded view provides a visual representation of the projector's components and their assembly order. Key parts are identified by numbers:

• 300: Top Case
• 320: Front Cover
• 400: Bottom Cover
• 500: Remote Control (AR2)
• 510: Power Supply Unit
• 530: Rear Cover
• 540: Side Panel
• 550: Main Board (Ass'y)
• 560: Speaker Module
• 570: USB/HDMI Board
• 590: Tuner Module
• 600: Main Chassis
• 700: Power Supply Unit (Internal)
• 800: Main Board
• 100: Front Panel
• 130: IR/Keypad Board
• 310: Side Cover

[!]

Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by [!] in the EXPLODED VIEW. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer.

DISASSEMBLY GUIDE

Follow these steps to disassemble the projector:

1. Remove the four screws securing the top case.
2. Separate the bottom case from the main chassis, noting the hook structure.
3. Carefully separate the rear case from the top case. It may be necessary to spread both sides to prevent damage to the top case's hooks.
4. Remove the four screws from the mid-case.
5. Separate the engine assembly from the top case.
6. Remove the screws and separate the main Printed Circuit Board (PCB).
7. Remove the top case's four screws.
8. Separate the engine assembly from the middle case. Disassembly is now complete.

ASSEMBLY GUIDE

Follow these steps to reassemble the projector. Key indicators: ? = Hook, ? = Screw.

1. Middle case + Engine: Secure with Φ3 screws (4 pieces).
2. Joystick + Middle case: Secure with Φ2 screws (2 pieces).
3. Jack B/D + Middle case: Secure with Φ2.6 screws (3 pieces).
4. Middle case + Fan + Speaker: Assemble these components.
5. Middle Case + Combo Assemble: Connect the Combo module (WIFI/Bluetooth) to the Middle Case.
6. Main B/D + Middle case: Secure with Φ2.6 screws (5 pieces).
7. Middle case + Top Case: Secure with Φ2.6 screws (4 pieces).
8. Rear Bracket + Top Case: Assemble the rear bracket to the top case.
9. Bottom Assy: Secure with Φ2.6 screws (4 pieces).

TROUBLE SHOOTING GUIDE

1. Poor Connection - Main, LED Board Ass'y

The following table lists common connection issues on the Main and LED Board Assembly:

Board connection points diagram: Shows the main board with numbered connection points (1-9) corresponding to the table below.

1. Poor Connection - LD Driver, Jack Board Ass'y

The following table lists common connection issues on the LD Driver and Jack Board Assembly:

Board connection points diagram: Shows the LD Driver and Jack Board assemblies with numbered connection points (9-11) corresponding to the table below.

2. Flow Chart for major symptom

This flowchart guides troubleshooting based on observed symptoms:

• SET problem occurrence:
• SET Power On?
  • No: Check power cord connection. After pulling out the adapter DC Plug, check Adapter Power 19V. If no, Adapter replacement.
  • Yes:
  • Joystick LED Works?
    • Yes: Set turn off Automatically?
      • Yes: Temp problem Or Fan problem?
        • 'Temp': High temp Error / Ambient Temp Err. Checks: FAN connection Check, FAN defect check, Main b/d defect check.
        • 'FAN': FANx Error ('x' is Fan No.). Checks: FAN connection Check, FAN defect check, Main b/d defect check.
      • No: Broken image (Vertical / parallel bar). Checks: DMD Cable check, Engine replacement, Main b/d defect check.
    • No: A Light Source turned on?
      • Yes: A light source on but No image. Checks: DMD connection check, Main b/d defect check.
      • No: A light source does not turn on. Checks: Driver B/D Defect Check, Main B/D defect check.

※ To check the Phenomena, Please check "power off status" in the In-Start mode as quickly as possible while Set working.