Installing an aftermarket car stereo in your Acura NSX can significantly upgrade your driving experience, bringing modern features and improved audio quality. Pioneer head units are a popular choice, known for their performance and versatility. However, wiring a new head unit into a classic car like the NSX requires careful attention to ensure compatibility and proper function. This guide provides a detailed Pioneer Car Stereo Wiring Harness Diagram specifically tailored for NSX models, along with troubleshooting tips and advice for a successful installation.
Understanding the NSX Wiring Harness and Pioneer Compatibility
The original NSX audio system utilizes a unique wiring configuration. When replacing the factory head unit with a Pioneer model, a wiring harness adapter is crucial. This adapter bridges the gap between the NSX’s proprietary connectors and the industry-standard connections on your Pioneer stereo, simplifying the installation process and preventing damage to your car’s original wiring. The diagram below outlines the correct connections when using a specific adapter, the SoS ipp-758, with a Pioneer AVIC-8100NEX head unit as an example. While the AVIC-8100NEX is an older model, the wiring principles generally apply to many modern Pioneer head units. Always consult your Pioneer head unit’s installation manual for specific wire color codes and functions.
| **Terminal** | **Wire** | **Connects To** | **SoS ipp-758** | [**AVIC-8100NEX**](http://www.pioneerelectronics.com/StaticFiles/Manuals/Car/AVIC-8100NEX_InstallationManual021915.pdf) |
|---|---|---|---|---|
| A1 | WHT | Passenger’s door speaker amp + | Red RCA-Male (gray wire “Right Front+” ) | Front Right RCA-Female |
| A2 | WHT | Driver’s door speaker amp+ | **Black RCA-Male (white wire “Left Front +”)** | Front Left RCA-Female |
| A3 | Red/Blk | Lights-on signal (dash and console lights) | ORANGE (“Dash light illumination”) | Orange/White - pwr cord #1 (page 8) |
| A4 | wht/yel | Constant power | YELLOW (“battery/constant 12v+”) | Yellow - pwr cord #1 (page 8) |
| A5 | Yel/Red | ACC (II) main stereo power | RED (“ignition switch 12v+”) | Red - pwr cord #1 (page 8) |
| A6 | Pnk/wht | Radio switch pwr (to antenna & relay) | BLUE (“power antenna”) | Blue/White(System Remote Control) - pwr cord #1 (page 9) To auto-antenna relay control terminal or antenna booster power control terminal (max. 300 mA 12 V DC). If the vehicle has a glass antenna, connect to the antenna booster power control terminal (max. 300 mA 12 V DC) |
| A7 | WHT | Driver Foot well base speaker (+) | Black RCA-Male (green wire “Left Rear +”) | Left Rear RCA-Female |
| A8 | WHT | Passenger foot well base speaker (+) | Red RCA-Male (Purple wire “Right Rear +”) | Right Rear RCA-Female |
| A9 | ORN | Passenger door speaker amp (-) | Red RCA-Male (gray blk wire “Right Front -”) | Right Front RCA-Female |
| A10 | ORN | Driver door speaker amp (-) | **Black RCA-Male (white blk wire “Left front -”)** | Front Left RCA-Female |
| A11 | Orn/wht | cell phone mute signal (not applicable) | empty | N/A |
| A12 | blk/brn | Security (IN) - This goes to NSX Security control Unit. No need to connect this. | empty | N/A |
| A13 | blk/lt grn | Security ground (G404) | empty | N/A |
| A14 | blk | Ground | Black (“Chassis Ground 12V-”) | Black - pwr cord #1 (page 8). |
| A15 | ORN | Driver Foot well speakers (-) | Black RCA-Male (green/blk wire “Left Rear -”) | Left Rear RCA-Female |
| A16 | ORN | Passenger foot well speaker(-) | Red RCA-Male (purple/blk wire “Right Rear - “) | Right Rear RCA-Female |Pioneer Car Stereo Wiring Harness Diagram for NSX with SoS ipp-758 Adapter
Key Considerations from the Wiring Diagram:
- Speaker Connections: The NSX uses amplified speakers. The diagram clearly maps the positive (+) and negative (-) speaker outputs from the NSX harness (Terminals A1, A2, A7, A8, A9, A10, A15, A16) to the RCA inputs of the Pioneer head unit via the SoS adapter. Pay close attention to polarity to ensure proper sound reproduction.
- Power and Illumination: Terminals A3, A4, A5, and A6 handle essential power functions.
- Constant Power (A4): Keeps the radio memory and clock running.
- ACC Power (A5): Turns the radio on and off with the ignition.
- Illumination (A3): Dims the radio display when the headlights are turned on.
- Power Antenna/Remote Turn-On (A6): Signals the power antenna or amplifier to turn on.
- Ground (A14): A solid ground connection is critical for minimizing noise and ensuring proper electrical function. Connect this securely to the vehicle chassis.
- Unused Terminals: Terminals A11, A12, and A13 are listed as not applicable or not needing connection in this setup. These relate to features not typically used in a standard aftermarket head unit installation in the NSX (like cell phone mute or factory security system integration in this context).
Troubleshooting Common Installation Issues
Even with a wiring diagram, you might encounter some challenges during your Pioneer car stereo installation in an NSX. Here are solutions to common problems:
1. Turn On/Off Thump and Speaker Hiss
Annoying noises like a “thump” when turning the system on or off, or a constant hiss from the speakers, are often signs of ground loop issues or signal interference.
- Grounding Issues: Double-check your Pioneer head unit’s ground connection (Terminal A14). Ensure it’s firmly connected to a clean, unpainted metal part of the NSX chassis. A poor ground is a frequent cause of noise.
- Noise Isolators: While you’ve already tried PAC SNI-1 noise isolators, they are a good step. Ensure they are installed correctly inline with the RCA outputs as you mentioned. If the hiss and thump are only attenuated and not eliminated, consider:
- Higher Quality Isolators: Some isolators are more effective than others. Research models known for better noise reduction.
- Gain Settings: Incorrect gain settings on the Pioneer head unit or any external amplifiers (if you have them) can amplify noise. Review your head unit’s manual for proper gain adjustment procedures.
- RCA Cable Quality and Routing: Use shielded RCA cables and route them away from power wires to minimize interference.
2. Mounting Bracket Solutions for Pioneer Head Units in NSX
Fitting a double DIN Pioneer head unit into the NSX’s center console can be tricky. The original poster mentioned the SoS 2DIN mounting bracket not being ideal. Here are alternative approaches:
- Universal Double DIN Brackets: Explore universal double DIN mounting brackets. These often offer more flexibility for custom installations and can be adapted to fit the NSX’s console. You might need to modify the bracket slightly for a perfect fit.
- Custom Mounting Plate: As the original poster suggests, a simple mounting plate might be sufficient. You could fabricate a plate from metal or sturdy plastic to securely hold the Pioneer head unit in place within the console opening. Consider using the original radio mounting points if possible for stability.
- Professional Installation: If you’re uncomfortable with custom fabrication, a professional car audio installer experienced with classic cars or sports cars like the NSX can create a custom mounting solution.
3. Cutting the Double DIN Slot in the SoS Center Console
Modifying the SoS center console to accommodate a double DIN unit requires careful execution, especially if you want to avoid cracking the material.
- Dremel with Cutting Bits: A Dremel rotary tool with appropriate cutting bits is indeed a suitable tool for this task. Use plastic cutting bits designed for smooth cuts.
- Masking and Marking: Precisely mark the double DIN opening on the console. Use masking tape around the cut area to protect the surrounding surface and provide a clear cutting guide.
- Slow and Steady Cutting: Don’t rush the cutting process. Work slowly and gradually, making multiple passes rather than trying to cut through the material in one go. This helps prevent cracking and ensures a cleaner cut.
- Sanding and Finishing: After cutting, use sandpaper to smooth the edges of the new opening for a professional finish.
4. Aspirator Fan Mount for Climate Control
The aspirator fan is important for the NSX’s automatic climate control system as it draws cabin air across the temperature sensor.
- Relocating the Fan: If the new head unit installation interferes with the original fan location, you’ll need to relocate it.
- Custom Mount: You can fabricate a small bracket to mount the aspirator fan in a nearby location behind the center console where it can still draw cabin air effectively. Ensure it’s not blocked by other components.
- Consider Airflow: Think about airflow when relocating the fan. It needs to be positioned where it can accurately sense the cabin temperature.
5. Integrating Ports into the Ashtray Slot
Routing USB, HDMI, and AUX ports to the ashtray area is a clever way to maintain a clean look while keeping these connections accessible.
- Ashtray Modification: The ashtray housing can be modified to create a custom faceplate for your ports.
- Custom Faceplate: You can fabricate a faceplate from plastic or metal that fits into the ashtray slot. Drill holes in the faceplate to accommodate your USB, HDMI, AUX, and microphone ports.
- Cable Routing: Carefully route the necessary cables from the back of the Pioneer head unit to the ashtray area. Ensure the cables are long enough and are routed safely to avoid pinching or damage.
- Pre-made Solutions: Explore if any pre-made faceplates or kits are available for routing ports to car ashtray locations. While NSX-specific solutions might be rare, generic car audio accessories might be adaptable.
Conclusion
Upgrading your Acura NSX with a Pioneer car stereo offers a fantastic blend of classic car charm and modern technology. By carefully following the wiring diagram, addressing potential installation challenges with the solutions provided, and paying attention to detail, you can achieve a professional-sounding and aesthetically pleasing car audio upgrade while respecting the originality of your NSX. Remember to always prioritize safety and consult professional installers if you are unsure about any aspect of the installation process.
Alt text: Detailed Pioneer car stereo wiring harness diagram for Acura NSX, illustrating connections between the 16P NSX connector and the SoS ipp-758 adapter to a Pioneer AVIC-8100NEX head unit, highlighting speaker, power, and ground connections for a successful aftermarket car audio installation.
