S3-1 Multi-Platform Stereo Replacement with Steering Wheel Control Interface

Product Overview

The Scosche S3-1 interface allows replacement of factory OEM stereos while retaining essential safety and warning features, as well as original steering wheel controls (if equipped).

Steering Wheel Controls

No steering wheel programming is required. The S3-1 Interface has built-in protocols for popular aftermarket stereos including: Alpine, Kenwood, Clarion, Pioneer, JVC, Sony.

S3-1 Installation Harnesses*

A vehicle-specific harness is required for installation (sold separately). Verify vehicle compatibility using the list included with the vehicle-specific harness.

• S3CR02: 2005-10 Select Chrysler S3-1 harness
• S3CR04: 2007-UP Select Chrysler S3-1 harness
• S3FD23: 2005-UP Select Ford, Linc, Merc S3-1 harness
• S3GMCL2: 2003-UP Select GM Class II S3-1 harness
• S3GM11C: 2004-UP Select GM LAN11 24Pin S3-1 harness
• S3GM11L: 2006-UP Select GM LAN11 14/16Pin S3-1 harness
• S3GMLAN: 2006-UP Select GM LAN29 14/16 Pin S3-1 harness
• S3TA03: 2004-UP Select Toyota JBL S3-1 harness

Preliminary S3-1 Functionality by Vehicle Platform

Before Beginning: Read This Instruction Manual

⚠️ Disconnect the negative battery terminal to avoid short circuits. Read ALL vehicle manufacturer's warnings regarding airbags and electrical systems. We recommend using ONLY a volt/ohm meter when checking/testing vehicle wiring. A test light (grounded probe type) can damage a vehicle's computer and/or electronics systems.

Component Overview

The S3-1 system includes a Steering Wheel Control Module and an S3-1 Interface Module. The Steering Wheel Control Module connects to the aftermarket stereo via a 3.5mm audio jack (for Alpine, Clarion, JVC, Pioneer, Sony) or a blue wire (for Kenwood). The S3-1 Interface Module connects to the vehicle's wiring harness.

Installation Overview

This section details the wiring connections between the aftermarket stereo, the S3-1 interface, and the vehicle.

Wiring Diagram Description

The diagram shows the Aftermarket Stereo connecting to the S3-1 Main Module via the S3-1 Vehicle-Specific Wire Harness. The Steering Wheel Module connects to the S3-1 Main Module. Output connections from the S3-1 Main Module include a 3.5mm Steering Wheel Output Cable (for specific brands) and a Blue Steering Wheel Output Wire (for Kenwood).

Wire Color Codes

Navigation Connections

• Violet/White: VSS Vehicle speed pulse signal
• Red/White: Reverse light trigger (+12V when in reverse gear)
• Yellow/Black: Parking brake trigger (-12V when park brake ON)
• Orange/White: Auto illumination (Data controlled lighting output on some GM LAN applications with AUTO headlights enabled)

Note: The RED Accessory output wire is rated at 10A Max. Connecting additional +12V switched accessories is not recommended and may damage the S3-1 module. A relay is needed if 10A output is insufficient (relay not included). Illumination & auto illumination outputs are for head unit connections only.

S3-1 Speaker / Audio Connections

RCA Low Level: For GM Bose (Excludes Prem. Bose), Ford Premium Sound, Toyota JBL/Lexus.

Speaker Wire (Cut-off RCAs): For Chrysler, Ford (Non-Premium), GM Bose (Non-Bose).

ATTN: All Ford Harness RCA cutting must be performed on the vehicle side of the circuit board.

Basic Wiring Instructions

Follow these general steps. Consult your vehicle-specific S3-1 harness instructions for detailed information.

1. Disconnect the negative battery cable to avoid short circuits.
2. Remove and unplug the factory stereo.
3. Match and connect the Power/ground wires from the S3-1 Vehicle specific harness to the wires provided with your stereo. Scosche harness color codes are designed to match most aftermarket stereos. Note that some wires for your new stereo come from the S3-1 interface box itself, not the vehicle connectors.
4. The S3-1 speaker connections are pre-terminated with RCA jacks for installations requiring Line input (Toyota JBL, GM Standard Bose, Ford Premium sound).
5. If your vehicle does not have a Bose or Premium system, cut off the RCAs and wire the speaker leads directly to the speaker wires from the new stereo.
6. All FORD harnesses must have RCAs cut on the vehicle side of the circuit board.
7. Tape any unused wiring to prevent short circuits.
8. Reconnect the negative battery cable.
9. For GM vehicles, alternate power-up (initialization steps) are required. Refer to General Motors specific notes.
10. As you install your new stereo, place the S3-1 module(s) and harnesses in the rear dash cavity behind the stereo.

Optional: Cable ties or double-sided tape can be used to secure the module (not included).

Vehicle-Specific Notes

Chrysler & Toyota Installation Notes

Chrysler: Premium Alpine, Boston & Infinity Systems

These factory amplified sound systems are driven and digitally controlled by a single set of left/right input channels. The aftermarket radio cannot control fade or balance adjustments on these systems. There is NO front/rear fader control; balance and fader are set to center by interface control software.

Toyota JBL / Lexus Premium Systems

These factory amplified sound systems are driven and digitally controlled by a single set of left/right input channels. The aftermarket radio cannot control fader on these systems. There is NO front/rear fader control; fader is set to center by interface control software.

General Motors Installation Notes

How to Test for "Premium Bose" Systems

Two types of Bose systems exist in GM vehicles. The S3-1 is not compatible with Digital Premium BOSE (y91/z75 systems). To test for digital Bose systems, rapidly turn the factory radio volume up and down. If the sound reacts immediately, it's Standard Bose. A slight delay indicates Premium Bose. Alternatively, check the glove box service parts code sticker for "y91" or "z75" equipment codes.

S3-1 General Motors Integrated Safety & Warning Chimes

Replacing the factory stereo in a GM vehicle with the S3-1 interface will replace portions of audible SAFETY and WARNING CHIME systems. Removing the stereo without the proper accessory will result in LOST functions. The vehicle's ECM (Electronics Control Module) will store an error code if operated without the factory radio, potentially causing service difficulties. The Scosche S3-1 sends proper data commands to the ECM to indicate a "healthy" status for diagnostic purposes.

Warning & Safety Chimes List:

• Parking assist
• Lights left on reminder
• Turn signal click
• Low fuel
• Seatbelt warning chime
• Check engine/service indicator
• Key left in ignition reminder

Power Up (Initialization Procedure)

To ensure proper functionality of the S3-1's +12V RED Accessory wire, follow this procedure:

1. Disconnect the Scosche Interface from the vehicle radio harness.
2. Close all doors and hood. Turn off all lights and remove keys from the ignition.
3. Wait 3 to 4 minutes (without opening a door, turning on a light, or inserting keys).
4. Connect the Scosche Interface to the vehicle's radio harness and start the vehicle.
5. Test interface functionality.

Steering Wheel Module Setup

The Scosche S3-1 offers "plug and play" steering wheel control setup, requiring no complicated learning, programming, or splicing. Setup is completed in seconds. (Tool provided by Scosche.)

1. Break off the small flat blade adjustment driver from the side of the steering wheel module housing as shown in the illustration.
2. Carefully turn the selector (arrow) dial to the correct letter corresponding to your aftermarket stereo brand: A=Alpine, C=Clarion, J=JVC, K=Kenwood, P=Pioneer, S=Sony.
3. Connect the steering wheel control module harness to the Main S3-1 interface via the 10-Pin connector. (Not shown)
4. Plug the 3.5mm connector into the "Remote" jack on the back of your aftermarket stereo. For Kenwood, connect the Blue wire to the radio's remote control input wire. (Not shown)

Steering Wheel Controls

Chrysler / Dodge / Jeep Version 1 (2005-08)

Steering Wheel Legend: SEEK UP, PRESET, VOLUME, SEEK DOWN, SOURCE, VOLUME

Chrysler / Dodge / Jeep Version 2 (2009-UP)

(Uses controls on BACK of Steering wheel ONLY)

Steering Wheel Legend: VOL UP, SEEK UP, SOURCE, PRESET, VOL DOWN, SEEK DOWN

Volume control note: Press once: up/down (one increment); Press and hold: up/down (continuous)

General Motors LAN Steering Wheel Legend (2006-UP)

Steering Wheel Legend: SEEK UP/PRESET UP, MUTE, SOURCE, VOL UP, VOL DOWN, SEEK DN/PRESET DN

General Motors Class II Steering Wheel Legend

Steering Wheel Legend: SOURCE, SEEK UP/TRACK UP, MUTE, VOL UP, PRESET/BAND, SOURCE, VOL DOWN, SEEK DN/TRACK DN

General Motors GM LAN 11 Bit Steering Wheel Legend

Steering Wheel Legend: VOL UP, MUTE, VOL DOWN, SEEK UP/TRACK UP, SEEK DOWN/TRACK DOWN

Toyota Steering Wheel Legend

Steering Wheel Legend: VOLUME DOWN, VOLUME UP, SEEK DOWN/PRESET DOWN, SEEK UP/PRESET UP, SOURCE, MODE

Volume control note: Press once: up/down (one increment); Press and hold: up/down (continuous)

Ford Steering Wheel Legend

Steering Wheel Legend: VOL DOWN, VOL +, VOL UP, SEEK DOWN, MEDIA or SOURCE, SEEK UP

Volume control note: Press once: up/down (one increment); Press and hold: up/down (continuous)

Steering Wheel Notes & Troubleshooting

Steering Wheel Control Notes & Exceptions

Illustrations of steering wheel controls are "typical". Actual controls and placement vary by make, model, trim level, and options package, but overall operation is similar. Volume UP/DOWN: Pressing once increments/decrements by one step; pressing and holding provides continuous adjustment. CD Seek UP/DOWN: Pressing once skips tracks; pressing and holding fast forwards/rewinds. Radio seek UP/DOWN operation varies; it may skip to the next strong station or cycle through memory presets. Consult your specific brand/configuration pages.

Troubleshooting

Stereo will not respond to Factory steering controls:

Verify vehicle compatibility. Check the S3-1 harness instruction for your particular vehicle listing.

Verify / Check Installation:

1. Check connections at the S3-1 module; verify power and ground are present.
2. Ensure the steering wheel control module is properly connected to the main S3-1 module.
3. Verify the steering wheel OUTPUT wire or 3.5mm cable is connected to the correct steering wheel INPUT on the back of the aftermarket stereo.
4. Confirm the steering wheel selection potentiometer is set to match the aftermarket radio brand (e.g., A: Alpine, C: Clarion, J: JVC, K: Kenwood, P: Pioneer, S: Sony - see page 3).