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Home >> Lexus >> 2009 >> IS F >> Repair and Diagnosis >> Accessories & Equipment >> Infotainment >> Navigation (Diagnostics - Introduction) >> Navigation System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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DISPLAY FUNCTION

Symptom Suspected Area See
Pressing PWR switch does not turn on system. Proceed to "Pressing Power Switch does not Turn ON System" Refer to Pressing Power Switch does not Turn on System
Multi-display power source circuit Refer to Multi-display Power Source Circuit
AVC-LAN circuit Refer to AVC-LAN Circuit
Multi-display Refer to REMOVAL
Black screen (No image appears on navigation/audio screen). Proceed to "No Image Appears on Multi-display" Refer to No Image Appears on Multi-display
Multi-display power source circuit Refer to Multi-display Power Source Circuit
Illumination circuit Refer to Illumination Circuit
AVC-LAN circuit Refer to AVC-LAN Circuit
Multi-display Refer to REMOVAL
Illumination for panel switch does not come on with TAIL switch on. Proceed to "Illumination for Panel Switch does not Come on with Tail Switch ON" Refer to Illumination for Panel Switch does not Come on with Tail Switch ON
Illumination circuit Refer to Illumination Circuit
Multi-display Refer to REMOVAL
Display does not dim (Night Screen) with TAIL switch on. Proceed to "Display does not DIM when Light Control Switch is Turned ON" Refer to Display does not Dim when Light Control Switch is Turned ON
Illumination circuit Refer to Illumination Circuit
Multi-display Refer to REMOVAL
Power does not turn off (The screen remains on). Multi-display power source circuit Refer to Multi-display Power Source Circuit
Multi-display Refer to REMOVAL
Panel switches do not function. Proceed to "Panel Switches do not Function" Refer to Panel Switches do not Function
Steering pad switch circuit Refer to Steering Pad Switch Circuit
Multi-display power source circuit Refer to Multi-display Power Source Circuit
Multi-display Refer to REMOVAL
Touch panel switch does not function. Proceed to "Touch Panel Switch does not Function" Refer to Touch Panel Switch does not Function
Steering pad switch circuit Refer to Steering Pad Switch Circuit
Multi-display power source circuit Refer to Multi-display Power Source Circuit
Multi-display Refer to REMOVAL
Navigation screen is not displayed. Proceed to "Display Signal Circuit between Navigation ECU and Multi-display" Refer to Display Signal Circuit between Navigation ECU and Multi-display
Map disc -
Navigation ECU Refer to REMOVAL
Multi-display Refer to REMOVAL
Navigation screen flicker or color distortion. Proceed to "Screen Flicker or Color Distortion" Refer to Screen Flicker or Color Distortion
Proceed to "Display Signal Circuit between Navigation ECU and Multi-display" Refer to Display Signal Circuit between Navigation ECU and Multi-display
Navigation ECU Refer to REMOVAL
Multi-display Refer to REMOVAL
DVD image cannot be displayed on multi-display. (Parking brake is on.)*1 Proceed to "Display Signal Circuit between Multi-display and Radio Receiver" Refer to Display Signal Circuit between Multi-display and Radio Receiver
Parking brake switch circuit Refer to Parking Brake Switch Circuit
Radio Receiver Refer to REMOVAL
Multi-display Refer to REMOVAL
Navigation function switches can be operated while vehicle is running. Proceed to "Vehicle Speed Signal Circuit between Multi-display and Combination Meter" Refer to Vehicle Speed Signal Circuit between Multi-display and Combination Meter
NAVIGATION FUNCTION

Symptom Suspected Area See
Map disc cannot be inserted. Proceed to "Map Disc cannot be Inserted" Refer to Map Disc cannot be Inserted
Navigation ECU power source circuit Refer to Navigation ECU Power Source Circuit
Navigation ECU Refer to REMOVAL
Map disc cannot be ejected. Proceed to "Map Disc cannot be Ejected" Refer to Map Disc cannot be Ejected
Navigation ECU power source circuit Refer to Navigation ECU Power Source Circuit
Navigation ECU Refer to REMOVAL
Vehicle position mark deviates greatly. Proceed to "Vehicle Position Mark Deviates Greatly" Refer to Vehicle Position Mark Deviates Greatly
GPS antenna Refer to REMOVAL
Navigation ECU Refer to REMOVAL
Cursor or map rotates when vehicle is stopped. Proceed to "Cursor or Map Rotates when Vehicle is Stopped" Refer to Cursor or Map Rotates when Vehicle Stopped
Navigation ECU Refer to REMOVAL
Vehicle position mark is not updated. Proceed to "Vehicle Position Mark is not Updated" Refer to Vehicle Position Mark is not Updated
Map disc -
Navigation ECU Refer to REMOVAL
Current position display does not appear. Proceed to "Current Position Display does not Appear" Refer to Current Position Display does not Appear
Map disc -
GPS antenna Refer to REMOVAL
Navigation ECU Refer to REMOVAL
GPS Mark is not displayed. Proceed to "GPS Mark is not Displayed" Refer to GPS Mark is not Displayed
GPS antenna Refer to REMOVAL
Navigation ECU Refer to REMOVAL
Voice guidance does not function. Proceed to "Voice Guidance does not Function" Refer to Voice Guidance does not Function
Navigation voice circuit Refer to Navigation Voice Circuit
Map disc -
Navigation ECU Refer to REMOVAL
Stereo component amplifier Refer to REMOVAL
Map display incomplete. Proceed to "Map Display Incomplete" Refer to Map Display Incomplete
Map disc -
Navigation ECU Refer to REMOVAL
Route cannot be calculated. Proceed to "Route cannot be Calculated" Refer to Route cannot be Calculated
Map disc -
Navigation ECU Refer to REMOVAL
Voice recognition difficulty. Proceed to "Voice Recognition Difficulty" Refer to Voice Recognition Difficulty
Navigation ECU Refer to REMOVAL
Voice is not recognized. Proceed to "Voice is not Recognized" Refer to Voice is not Recognized
Proceed to "Microphone circuit between Overhead J/B and Multi-display" Refer to Microphone Circuit between Overhead J/B and Multi-display
Proceed to "Microphone circuit between Multi-display and Navigation ECU" Refer to Microphone Circuit between Multi-display and Navigation ECU
Steering pad switch circuit Refer to Steering Pad Switch Circuit
Microphone Refer to REMOVAL
Microphone amplifier Refer to REMOVAL - Step 3
Navigation ECU Refer to REMOVAL
Speed signal does not change in the navigation check mode. Proceed to "Vehicle Speed Signal Circuit between Navigation ECU and Multi-display" Refer to Vehicle Speed Signal Circuit between Navigation ECU and Multi-Display
Reverse signal does not change in the navigation check mode. Proceed to "Reverse Signal Circuit" Refer to Reverse Signal Circuit
STEERING PAD SWITCH FUNCTION

Symptom Suspected Area See
The system cannot be operated by the steering pad switch. Steering pad switch circuit Refer to Steering Pad Switch Circuit
Radio receiver Refer to REMOVAL
Illumination for steering pad switch does not come on with tail switch on. Illumination circuit Refer to Illumination Circuit
Radio receiver Refer to REMOVAL
"BLUETOOTH" FUNCTION

Symptom Suspected Area See
Cellular phone registration failure, phone directory transfer failure. Proceed to "Cellular Phone Registration Failure, Phone Directory Transfer Failure" Refer to Cellular Phone Registration Failure, Phone Directory Transfer Failure
Cellular phone cannot send/receive. Proceed to "Cellular Phone cannot Send/Receive" Refer to Cellular Phone cannot Send/Receive
Steering pad switch circuit Refer to Steering Pad Switch Circuit
Radio receiver Refer to REMOVAL
Cannot call in a certain place. Proceed to "Cannot call in a Certain Place" Refer to Cannot Call in a Certain Place
The other caller's voice cannot be heard, is too quiet, or distorted. Proceed to "The Other Caller's Voice cannot be Heard, is too Quiet, or Distorted" Refer to The Other Caller's Voice cannot be Heard, is too Quiet, or Distorted
Multi-display Refer to REMOVAL
The other caller cannot hear your voice, or your voice is too quiet or distorted. Proceed to "The Other Caller cannot Heard Your Voice, or Your Voice is too Quiet or Distorted" Refer to The Other Caller cannot Hear Your Voice, or Your Voice is too Quiet or Distorted
Proceed to "Microphone circuit between Overhead J/B and Multi-display" Refer to Microphone Circuit between Overhead J/B and Multi-display
Microphone Refer to REMOVAL
Microphone amplifier Refer to REMOVAL - Step 3
Multi-display Refer to REMOVAL