Bose Lifestyle 20 Repair Manual

The Bose Lifestyle 20 is a premium home theater system featuring an Acoustimass module, jewel cube speakers, and a central media console. This repair manual provides detailed instructions for troubleshooting, disassembly, component replacement, and testing procedures for authorized service personnel. Below are key sections covering safety, system overview, diagnostic procedures, part replacement, and calibration.

System Overview

Key components: Media Console (Control Unit), Acoustimass Bass Module, Five Jewel Cube Speakers, Remote Control, Power Cables, and Connection Harnesses.

Safety Precautions

Before performing any repair, ensure the system is disconnected from AC power. Use appropriate ESD protection.

1. Disconnect Power: Unplug the media console and bass module from wall outlets.
2. ESD Protection: Use grounded wrist strap when handling circuit boards.
3. Component Handling: Avoid touching capacitors; they may retain charge.
4. Work Area: Use clean, well-lit, static-free surface for disassembly.

WARNING! High voltages are present inside the media console and bass module. Only qualified personnel should perform internal repairs.

Diagnostic Flowchart

Follow systematic troubleshooting to isolate faults.

1. No Power: Check AC outlet, power cord, internal fuse, and power supply board.
2. No Sound: Verify input selection, volume, mute status, and speaker connections.
3. Distorted Audio: Test individual channels, check amplifier board, and inspect speakers.
4. Remote Not Working: Replace remote batteries, check IR/RF sensor, test remote codes.
5. Display Issues: Check display panel connections and processor board output.

CAUTION! Do not apply power to the system with covers removed unless performing specific voltage measurements.

Technical Specifications

• System Type: 5.1 Channel Home Theater System.
• Total Power: 200 Watts RMS total system power.
• Frequency Response: 35Hz - 20kHz (±3dB).
• Inputs: Optical Digital, Coaxial Digital, Analog Stereo (RCA), Composite Video.
• Outputs: Proprietary speaker outputs, Subwoofer output, IR repeater.
• Power Requirements: 120V AC, 60Hz, 2.5A max.
• Dimensions (Console): 16.5" W x 3.5" H x 12.5" D.
• Operating Temperature: 41°F to 95°F (5°C to 35°C).

Disassembly Instructions

Media Console Disassembly:

1. Remove the four rubber feet from the bottom to access screws.
2. Remove all visible screws from the bottom panel.
3. Carefully separate the top cover from the chassis.
4. Disconnect internal ribbon cables and wiring harnesses noting their positions.
5. Remove the front panel assembly by releasing plastic clips.

Acoustimass Module Disassembly:

1. Place module face down on soft surface.
2. Remove screws around the perimeter of the back panel.
3. Lift off back panel to access internal components.
4. Label all wire connections before disconnecting.

Component Testing

Power Supply Testing:

1. Check AC input fuse with multimeter continuity test.
2. Measure DC output voltages: +5V, +12V, -12V, +24V rails.
3. Check for swollen capacitors or burnt components.

Amplifier Board Testing:

1. Check output transistors for shorts (collector to emitter).
2. Test speaker relay operation.
3. Measure DC offset at speaker outputs (should be < 50mV).

Speaker Testing:

1. Measure impedance of each jewel cube (should be approximately 4-6 ohms).
2. Check bass module driver and passive radiator for damage.

Common Replacements

Frequently replaced parts and their Bose part numbers:

Reassembly & Calibration

After component replacement:

1. Reconnect all cables and harnesses securely.
2. Reassemble chassis in reverse order of disassembly.
3. Power on system and check for normal operation.
4. Run system calibration using built-in ADAPTiQ audio calibration.
5. Test all inputs and speaker channels.
6. Verify remote control functionality.

Note: ADAPTiQ calibration requires the original headset microphone. Ensure proper placement during calibration process.

Error Codes

System displays error codes via flashing LED patterns:

Tools & Equipment

Required for repair:

• Phillips screwdrivers (#1, #2)
• Torx screwdriver set (T8, T10)
• Digital multimeter with capacitance test
• ESD wrist strap and mat
• Soldering iron with fine tip
• Desoldering pump or wick
• Needle-nose pliers
• Plastic spudger/pry tools
• Oscilloscope (for advanced diagnostics)
• Bose ADAPTiQ calibration microphone

Service Contacts

For genuine Bose parts and technical support:

• Bose Technical Support: 1-800-999-2673
• Bose Parts Department: 1-800-379-2073
• Online Support: www.bose.com/support
• Authorized Service Centers: Locate via Bose website
• Service Manual Updates: Check Bose professional portal

Warranty Note: Unauthorized repairs may void warranty. Verify warranty status before proceeding.