Upgrading your 2008 Toyota Prius from a standard JBL radio to a navigation system can significantly enhance your driving experience. However, it’s not a simple plug-and-play process. This guide outlines the necessary wiring modifications to successfully swap your 2008 Prius JBL radio with a navigation unit. Please note that this procedure requires careful attention to wiring diagrams and some experience with car audio systems.
This swap primarily involves rerouting several wires to ensure the navigation system functions correctly with your Prius. Below are the key wiring adjustments you’ll need to make. You will likely need to source additional connectors (E4, E5, E6) as these might not be present in your standard radio setup.
Wiring Modifications for Navigation Swap:
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Speed Wire: Connect the speed sensor wire to E5 pin 3. This is crucial for navigation accuracy as it informs the system about vehicle speed. You will need to acquire the E5 connector as it’s likely missing from the standard radio harness.
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TSW (Temperature Switch Wire): Move the wire from E14 pin 3 to E4 pin 12. This wire, related to temperature sensing, needs to be relocated for the navigation system. You will also need to source the E4 connector.
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S/MGND (Shield/Microphone Ground): Relocate the shield or microphone ground wire from E14 pin 6 to E4 pin 18. This ground wire is essential for audio signal integrity and microphone operation. Again, sourcing the E4 connector is necessary.
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AUX IN Wires: These wires are for auxiliary audio input. The following changes are required and you’ll need to source the E6 connector:
- AUXI/ADPG: Move from E3 pin 19 to E6 pin 6.
- VAL+/ALI: Move from E3 pin 17 to E6 pin 3.
- VAR+/ARI: Move from E3 pin 15 to E6 pin 2.
- VA-/ASGN: Move from E3 pin 16 to E6 pin 5.
- AGND: Move from E3 pin 18 to a chassis ground point. Ensure a solid ground connection for optimal audio performance.
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BLUETOOTH MIC: For Bluetooth microphone functionality, these wires need to be moved to the E4 connector:
- MACC/MCVD: Move from E14 pin 7 to E4 pin 17.
- MIC+: Move from E14 pin 2 to E4 pin 19.
- MIC-: Move from E14 pin 1 to E4 pin 20.
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Steering Pad Buttons: The steering wheel control buttons should use the same socket and pins between the navigation and standard radio systems. No changes are expected here.
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Parking Brake Signal Wire: Connect the parking brake signal wire to E5 pin 1. This signal is often used to enable or disable certain navigation features when the parking brake is engaged. If you prefer not to connect to the actual parking brake signal, you can use a switch connected to ground. Grounding this pin will simulate the parking brake being on for the radio. You will need to source the E5 connector.
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REV Signal (Reverse Signal): Connect the reverse signal wire to E5 pin 5. This 12V signal is activated when the car is in reverse. While technically optional if you retain the reverse camera display on the Multi-Function Display (MFD), connecting it to the navigation unit allows the navigation screen to display the reverse camera feed if configured to do so in the future. You will need to source the E5 connector.
Radio Specific Wire Removals:
- E14 pin 5 & E14 pin 16: These pins are specific to the standard radio and need to be removed for the navigation system to function correctly. They are radio-only connections and are not utilized by the navigation unit.
Connector Notes:
- E15 & E16: It’s believed that connectors E15 and E16 are physically the same socket but may have different colored plastic housings.
- E17 (Black Connector): The black connector you might encounter could be E17, which is typically for heated seats and not directly related to the radio swap. Pin 3 (orange wire) of this connector should be 12V when the car is running if it’s indeed pre-wiring for heated seats.
- Hazard Socket (E19): The hazard socket (E19) is an 8-pin connector and should be the same for both navigation and standard radio models. It does not connect to the back of the navigation unit itself.
Conclusion:
Swapping a 2008 Prius JBL radio with a navigation system requires careful wiring modifications and is not a plug-and-play upgrade. This guide provides the essential wiring changes based on available diagrams. It’s crucial to double-check all connections against your specific vehicle’s wiring diagrams and proceed with caution. If you are not comfortable with car audio wiring, it is highly recommended to seek professional installation to avoid damaging your vehicle’s electrical system or the new navigation unit.
