Aircraft Avionics Bench Testing, Diagnostics & Repair
When an aircraft avionics unit is malfunctioning, the first question should not automatically be:
“What should we replace?”
The first question should be:
“What is actually causing the problem?”
Apex Avionics Repair provides aircraft avionics bench evaluation, diagnostics, troubleshooting and repair support for individual aircraft owners, pilots, A&P mechanics, IAs, avionics shops, maintenance facilities, flight schools, flying clubs and fleet operators.
Bench evaluation can help determine whether a reported failure is actually inside the avionics unit or whether the problem may originate somewhere else in the aircraft.
For eligible equipment, customers throughout the United States can submit avionics through our nationwide mail-in repair program.
What Is Avionics Bench Repair?
Avionics bench repair involves removing an avionics component from the aircraft and evaluating it separately using appropriate test equipment, power sources and diagnostic procedures.
This allows the unit to be evaluated outside the aircraft installation.
Depending on the equipment and reported problem, bench evaluation may help identify issues involving:
- Power operation
- Internal electronics
- Displays
- Buttons
- Knobs
- Encoders
- Touchscreens
- Communication functions
- Navigation functions
- GPS operation
- Transponder operation
- Audio functions
- Intermittent faults
- Internal connections
- Previous repair work
- Physical damage
- Other equipment-specific functions
The goal is to determine whether the reported fault can be duplicated and whether the problem follows the avionics unit itself.
Why Bench Testing Matters
Aircraft avionics operate as part of a larger electrical and communication system.
A problem that appears to be coming from one piece of equipment may actually originate elsewhere.
Possible causes outside the avionics unit can include:
- Aircraft wiring
- Ground connections
- Circuit breakers
- Power supply
- Avionics rack
- Connector pins
- Antennas
- Coaxial cable
- Audio panel
- Push-to-talk wiring
- External sensors
- Configuration issues
- Other connected avionics
Bench testing helps separate the equipment from the aircraft installation.
If the fault follows the unit during bench evaluation, the problem is more likely to be internal to the equipment.
If the unit operates normally on the bench, troubleshooting may need to shift back to the aircraft.
Avionics Problems That May Benefit From Bench Evaluation
Bench evaluation can be useful for a wide range of avionics symptoms.
Unit Will Not Power On
A completely dead avionics unit may have an internal failure.
However, a no-power complaint can also originate from:
- Aircraft power
- Circuit breaker
- Ground connection
- Wiring
- Connector
- Avionics rack
- Internal power supply
- Internal electronics
Bench evaluation can help determine whether the unit powers and operates normally outside the aircraft.
Random Reboots or Intermittent Power
Intermittent avionics problems can be difficult to diagnose.
Symptoms may include:
- Random resets
- Unit shutting off
- Power cycling
- Unit restarting during engine start
- Display suddenly going blank
- Equipment working when cold but failing when warm
- Failure occurring only occasionally
A controlled bench environment may help reproduce these conditions and isolate the source.
Display & Screen Problems
Display failures are common on aging avionics.
Possible symptoms include:
- Dim display
- Blank screen
- Fading display
- Discoloration
- Horizontal lines
- Vertical lines
- Dead pixels
- Missing pixels
- Backlight failure
- Dark areas
- Flickering
- Intermittent display
- Display changes as the unit warms up
A display complaint does not always mean the display assembly itself has failed.
The problem may involve internal electronics, power circuitry, backlighting or another component.
Button, Knob & Encoder Problems
Avionics controls receive constant use and can develop mechanical or electronic faults.
Common complaints include:
- Button does not respond
- Button works intermittently
- Excessive pressure required
- Knob skips selections
- Encoder moves unpredictably
- Cursor jumps
- Knob turns without changing the selection
- Push function does not work
- Frequency selection is difficult
- Control behaves differently when warm
Bench evaluation can help determine whether the control issue is internal to the unit.
Communication Radio Bench Repair
COM radio complaints may include:
- Will not transmit
- Will not receive
- Weak transmission
- Weak reception
- Static
- Distorted audio
- Intermittent communications
- Poor audio quality
- Frequency selection problems
- Transmit works but receive does not
- Receive works but transmit does not
Because communication systems involve antennas, coaxial cable, connectors, audio panels and aircraft wiring, bench evaluation can help determine whether the fault is inside the radio or elsewhere in the aircraft.
GPS & Navigation Bench Testing
GPS and navigation problems can involve the avionics unit, antenna system or aircraft installation.
Reported problems may include:
- No GPS position
- Slow satellite acquisition
- Intermittent GPS signal
- Loss of navigation
- GPS warning messages
- VOR reception problems
- Localizer problems
- Glideslope problems
- NAV audio issues
- CDI or HSI interface problems
Testing the unit separately can help determine whether the equipment itself is responding normally.
Transponder Bench Repair
Transponder problems may include:
- Unit will not power on
- ATC cannot see the aircraft
- Intermittent replies
- Incorrect altitude reporting
- Mode C issues
- Mode S issues
- ADS-B related complaints
- Display or control problems
- Error messages
Some transponder issues may originate inside the equipment, while others may involve antennas, coax, wiring or connected altitude sources.
Bench evaluation is one part of determining where the fault originates.
Audio Panel Bench Repair
Aircraft audio systems can produce symptoms such as:
- No audio
- Weak audio
- Distorted audio
- Intermittent audio
- One headset position not working
- COM selection problems
- Intercom problems
- Microphone problems
- Push-to-talk complaints
Because an audio panel interacts with radios, headsets, microphones, PTT wiring and aircraft wiring, diagnosis may require separating the audio panel from the aircraft installation.
Garmin Avionics Bench Repair
Apex provides diagnostic and repair support for eligible Garmin avionics.
Garmin equipment submitted for bench evaluation may include:
Garmin GNS Series
- Garmin GNS 430
- Garmin GNS 430W
- Garmin GNS 530
- Garmin GNS 530W
Garmin GTN Series
- Garmin GTN 650
- Garmin GTN 650Xi
- Garmin GTN 750
- Garmin GTN 750Xi
Garmin G1000 Equipment
- GDU displays
- GIA units
- Other eligible G1000 components
Other Garmin Avionics
Eligible Garmin equipment may also include:
- GTX transponders
- GMA audio panels
- GNX navigators
- GPS navigators
- GNC units
- Electronic flight instruments
- Other Garmin avionics
Bench Repair for Other Avionics Brands
Apex also accepts inquiries for eligible avionics from other manufacturers.
Depending on the equipment, support may include products from:
- BendixKing
- Collins
- Avidyne
- Aspen
- S-TEC / Genesys
- Dynon
- L3Harris
- uAvionix
- Other aircraft avionics manufacturers
Available repair and test capability depends on the specific model, fault, equipment support status and component availability.
If you are unsure whether we can evaluate your unit, submit the model and problem description before shipping.
Bench Evaluation vs. Aircraft Troubleshooting
Bench testing and aircraft troubleshooting are not the same thing.
Bench Evaluation
Bench evaluation focuses on the removed avionics unit.
It may help determine whether the reported fault exists inside the equipment.
Aircraft Troubleshooting
Aircraft-level troubleshooting evaluates the installation and systems around the unit.
This may include:
- Aircraft wiring
- Power
- Grounds
- Circuit breakers
- Antennas
- Coaxial cables
- Connectors
- Racks
- Audio systems
- Sensors
- Interfaces
- Other connected avionics
If a unit tests normally on the bench, additional aircraft troubleshooting may be necessary.
Intermittent Avionics Problems
Intermittent avionics failures can be some of the most difficult problems to reproduce.
Before removing the unit, document as much information as possible.
Tell us whether the problem:
- Happens immediately after startup
- Appears after the unit warms up
- Occurs only during flight
- Happens during engine start
- Changes with vibration
- Happens when transmitting
- Appears when another avionics unit is turned on
- Disappears after cycling power
- Happens randomly
Photos or video of an intermittent fault can be extremely helpful.
What to Send With Your Avionics Bench Repair Request
The quality of the initial problem description can make a major difference.
Equipment Information
Provide:
- Manufacturer
- Model
- Part number when available
- Serial number
- Software version when relevant
Aircraft Information
Provide:
- Aircraft manufacturer
- Aircraft model
- Registration number when applicable
- Relevant avionics configuration
Describe the Exact Problem
Tell us:
- What does the unit do?
- What does it fail to do?
- Is the problem constant or intermittent?
- Does temperature affect it?
- Does vibration affect it?
- Does it happen during engine start?
- Does it happen only in flight?
- Are any error messages displayed?
- Has any troubleshooting already been performed?
Photos & Video
Upload photographs or video when they help demonstrate:
- Display problems
- Error messages
- Intermittent operation
- Control problems
- Physical damage
- Model and serial information
Nationwide Mail-In Avionics Bench Repair
Individual aircraft owners and aviation professionals throughout the United States can submit eligible avionics to Apex for mail-in evaluation.
How It Works
1. Submit a Repair Request
Provide your contact information, aircraft information, avionics model, serial number and detailed description of the problem.
2. Review
We review the information you submit and determine the appropriate next step.
3. Ship Your Avionics
If the unit is appropriate for mail-in evaluation, package it carefully and ship it to Apex.
4. Bench Evaluation
The unit is evaluated based on the reported problem and applicable service capability.
5. Determine the Repair Path
If the fault can be duplicated and a practical repair path exists, the appropriate next step can be determined.
6. Applicable Testing
Testing is completed based on the work performed and equipment involved.
7. Return
The equipment is prepared for return.
Individual Aircraft Owners Welcome
You do not need to be an avionics shop or maintenance facility to contact Apex.
We welcome individual aircraft owners and owner-pilots to work directly with us.
We also support:
- A&P mechanics
- IAs
- Avionics technicians
- Aircraft maintenance shops
- Flight schools
- Flying clubs
- Aircraft dealers
- Fleet operators
- Aviation businesses
Whether you own one aircraft or manage multiple airplanes, you can submit a repair request directly to Apex Avionics Repair.
Avionics Bench Repair in Orlando & Central Florida
Apex Avionics Repair is located in Apopka, Florida and supports aircraft owners and aviation businesses throughout the greater Orlando and Central Florida aviation community.
Local customers may contact us regarding eligible avionics bench repair and aircraft-level troubleshooting.
We serve customers from areas including:
- Orlando
- Apopka
- Sanford
- Kissimmee
- DeLand
- Daytona Beach
- Leesburg
- Ocala
- Lakeland
- Surrounding Central Florida airports
Nationwide mail-in service is available for eligible avionics equipment.
Why Choose Apex for Avionics Bench Repair?
Diagnose Before Replacing
Our approach begins by identifying what has actually failed before assuming a major avionics component needs replacement.
Unit-Level & Aircraft-System Thinking
Aircraft avionics do not operate in isolation.
When appropriate, we consider both the avionics unit and the aircraft systems connected to it.
Support for Legacy & Modern Avionics
Different generations of avionics require different diagnostic and repair strategies.
Direct Support for Aircraft Owners
Individual aircraft owners are welcome to contact Apex directly.
Nationwide Mail-In Service
Eligible avionics can be submitted from customers throughout the United States.
Central Florida Support
Aircraft-level troubleshooting and local avionics support are available for applicable work in the Orlando and Central Florida area.
Frequently Asked Questions About Avionics Bench Repair
What is avionics bench repair?
Avionics bench repair involves evaluating an avionics unit outside the aircraft using appropriate test equipment and diagnostic procedures.
Why should avionics be bench tested?
Bench testing can help determine whether a reported failure follows the avionics unit or whether the problem may exist elsewhere in the aircraft.
Can individual aircraft owners send avionics directly to Apex?
Yes. Individual aircraft owners and owner-pilots are welcome to work directly with Apex.
What types of avionics can be bench tested?
Depending on the model and available capability, eligible equipment may include GPS navigators, NAV/COM units, displays, transponders, audio panels, communication radios, navigation radios, electronic flight instruments and other aircraft avionics.
Can you bench test Garmin GNS 430 and GNS 530 units?
Apex provides diagnostics, troubleshooting and repair support for eligible Garmin GNS-series equipment including GNS 430, 430W, 530 and 530W units.
What if the avionics unit works normally on the bench?
That can be useful diagnostic information. If the unit performs normally during evaluation, troubleshooting may need to shift toward aircraft power, wiring, grounds, connectors, antennas, coax or other connected systems.
Should I send the rack or wiring harness?
Usually not unless requested. Submit a repair request first and provide the exact model and reported problem.
What information should I provide before shipping?
Provide the manufacturer, model, part number if available, serial number, aircraft information and detailed description of the failure.
Can I send photos or video?
Yes. Photos and video can be particularly helpful for display problems, error messages and intermittent faults.
Need Avionics Bench Repair?
Tell us what equipment you have and exactly what it is doing.
Provide:
- Manufacturer
- Model
- Part number
- Serial number
- Aircraft make and model
- Detailed problem description
- Error messages
- Photos or video when helpful
- Previous troubleshooting
We can use that information to help determine the appropriate next step.
Request Avionics Bench Repair
Individual Aircraft Owners Welcome
Aircraft Avionics • Bench Testing • Diagnostics • Repair Support