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- Feb 23, 2023
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If you're ready to modernize the radio setup in your 94-03 Grand Prix, ditch that old 1.5 DIN unit and upgrade to a double DIN touchscreen with Android Auto and Apple CarPlay — while keeping your steering wheel audio controls. Here's how to do it right.
- Look for a Dark Blue wire, usually in pin A7 of the 24-pin GM connector.
- This is the resistor-based steering wheel control signal.
To connect the SWC module:
1. Connect the Dark Blue wire to your SWC interface input.
2. Connect power (switched 12V), ground, and radio-specific control wires per your module instructions.
3. Program the module — Axxess ASWC-1 usually auto-detects both the car and radio. If not, follow manual programming steps.
Trim the radio opening: The Grand Prix’s 1.5 DIN slot must be enlarged vertically. Trim the plastic dash structure and possibly the back support bar for depth.
Install dash kit & head unit: Mount your head unit using the included brackets. Use the Metra kit as a trim bezel — trim to fit cleanly around your double DIN screen.
Wire it up: Connect the wiring harness adapter to your head unit and splice in the SWC module. Don’t forget the antenna adapter and mic/camera cables if needed.
Test everything: Power on the radio, test steering wheel buttons, Bluetooth, audio, etc. Secure all wiring and reinstall trim panels.
Parts Checklist
- Head Unit Options (All support Android Auto & CarPlay):
- • Pioneer DMH-W4660NEX (wireless AA/CarPlay, modular design)
- • Sony XAV-AX4000 (great UI, compact chassis)
- • Kenwood DMX7709S (customizable UI, reliable brand)
- Dash Kit:
- • Metra 95-2001 GM Double DIN Dash Kit (Trim to fit the Grand Prix dash)
- Wiring & Connectivity:
- • Metra 70-1858 GM wiring harness (already on hand)
- • Metra 40-GM10 antenna adapter (already on hand)
- Steering Wheel Control Interface (Pick one):
- • Axxess ASWC-1 — most flexible, auto-detects vehicle/radio
- • PAC SWI-RC — for resistor-based setups like this
Tools Needed
- Panel popper tool
- Rotary tool (Dremel) for dash trimming
- Soldering iron or crimp tools
- Wire stripper & tape
- Multimeter (for verifying SWC wires)
Wiring Overview
Factory SWC wire:- Look for a Dark Blue wire, usually in pin A7 of the 24-pin GM connector.
- This is the resistor-based steering wheel control signal.
To connect the SWC module:
1. Connect the Dark Blue wire to your SWC interface input.
2. Connect power (switched 12V), ground, and radio-specific control wires per your module instructions.
3. Program the module — Axxess ASWC-1 usually auto-detects both the car and radio. If not, follow manual programming steps.
Install Process
Remove factory radio & dash trim: Unclip the bezel and unscrew the OEM unit.Trim the radio opening: The Grand Prix’s 1.5 DIN slot must be enlarged vertically. Trim the plastic dash structure and possibly the back support bar for depth.
Install dash kit & head unit: Mount your head unit using the included brackets. Use the Metra kit as a trim bezel — trim to fit cleanly around your double DIN screen.
Wire it up: Connect the wiring harness adapter to your head unit and splice in the SWC module. Don’t forget the antenna adapter and mic/camera cables if needed.
Test everything: Power on the radio, test steering wheel buttons, Bluetooth, audio, etc. Secure all wiring and reinstall trim panels.
Final Tips
- If using a floating screen, make sure it clears your HVAC controls.
- Consider adding a backup cam or USB extension while you’re in there.
- Label your wiring connections — future you will thank you.
