Brand: SONY
Category: Audio
Document Type: Manual
Language: EN
Available Languages: EN , ES
Manual for CDX-GT450U
Uploaded: Nov. 21, 2025, 8:54 p.m.
Warranty Information
Consult your nearest Sony dealer for warranty information or if problems are not covered in this manual.
Getting Started
Playable Discs: This unit plays CD-DA (including CD TEXT) and CD-R/CD-RW discs containing MP3/WMA/AAC files.
Resetting the Unit: Before initial use, or after battery replacement, detach the front panel and press the RESET button.
Canceling DEMO Mode: Access the setup menu, navigate to DEMO, and select DEMO-OFF.
Setting the Clock: Access the setup menu, select CLOCK-ADJ, and set the hour and minute using the control dial and SEEK buttons.
Detaching/Attaching Front Panel: Press and hold SOURCE/OFF to turn off the unit, then detach the front panel. Reattach by engaging part A and pushing the left side until it clicks.
Radio
Storing Stations: Use Best Tuning Memory (BTM) for automatic storage or manually store stations using number buttons.
Receiving Stations: Select the band and press the corresponding number button.
Tuning: Use SEEK +/- for automatic or manual tuning.
CD/USB
Playback: Insert disc or connect USB device. Playback starts automatically or by selecting the source.
Display Items: Press DSPL to cycle through display information.
Repeat/Shuffle: Use REP and SHUF buttons to select playback modes.
Searching for a Track
Quick-BrowZer™: Search by name within CD or USB devices.
ZAPPIN™: Listen to short passages of tracks to find desired songs.
Troubleshooting and error codes
| Problem | Possible Cause and Solution |
|---|---|
| The unit does not power up. | Check connection or fuse. If the unit is turned off and the display disappears, turn the unit on. |
| The power antenna (aerial) does not extend. | The power antenna (aerial) does not have a relay box. |
| No sound is emitted. | ATT function is activated. The FADER control is not set for a 2-speaker system. |
| No beep sound. | Beep sound is canceled. An optional power amplifier is connected and the built-in amplifier is not in use. |
| Memory contents have been erased. | RESET button was pressed. Power supply lead or battery was disconnected. |
| Stored stations and correct time are erased. | The fuse has blown. |
| Noise when the ignition position is switched. | Cables are not correctly connected to the car's accessory power connector. |
| Demonstration mode starts during playback or reception. | If no operation is performed for 5 minutes with DEMO-ON set, DEMO mode starts. Set DEMO-OFF (page 17). |
| Display disappears or does not appear. | Dimmer is set to DIM-ON. Display disappears when SOURCE/OFF is pressed and held. Clean connectors (page 20). |
| Auto Off function is inoperable. | The unit is powered on. Auto Off activates when the unit is turned off. Turn the unit off. |
| Cannot tune in to stations. Sound is noisy. | Connection is incorrect. Connect electric antenna control cable (blue) or accessory power cable (red) if applicable. Check vehicle antenna connection. Check electric antenna control cable connection if the automatic antenna does not extend. |
| Cannot tune in to a preset station. | Frequency not stored correctly. Signal is too weak. |
| Automatic station tuning is impossible. | Local Seek Mode setting is incorrect. Set LOCAL-ON or LOCAL-OFF (page 18). Signal is too weak. Manually tune the frequency. |
| FM broadcast in stereo emits in mono (ST indicator flashes). | Tune to the correct frequency. Signal is too weak. Select MONO-ON (page 18). FM stereo is heard in mono. Select MONO-OFF (page 18). |
| RDS PTY display is blank. | Current station is not an RDS station. No RDS data received. Station does not indicate program type. |
| Cannot insert disc. | Another disc is already in place. Disc inserted forcefully, upside down, or in the wrong direction. |
| Disc playback does not start. | Disc is defective or dirty. CD-R/CD-RW discs not intended for audio use (page 20). |
| Cannot play MP3/WMA/AAC files. | Disc is not compatible with the MP3/WMA/AAC format or version. Visit support site for details. Playback of some MP3/WMA/AAC files may take longer due to complex folder hierarchy, multi-session discs, or discs with added data. Displayed information may not scroll for discs with many characters, AUTO SCR is set to OFF, or DSPL (SCRL) button not held. |
| Sound skips. | Installation is incorrect. Install the unit at an angle of less than 45° in a stable vehicle location. Disc is defective or dirty. |
| Control buttons do not function. | Cannot eject disc. Press RESET button (page 6). |
| Cannot play items using a USB hub. | This unit cannot recognize USB devices connected via a USB hub. |
| Cannot play certain items. | USB device not functioning. Reconnect it. Playback on USB device takes longer due to complex folder hierarchy. A beep is emitted if the USB device was disconnected during playback. Stop playback before disconnecting USB to avoid data damage. Sound may be intermittent at bitrates above 320 kbit/s. |