Wiring Color Reference
Common OEM wire color codes by manufacturer and system. Search by function or color.
| System | Function | Wire Color | Notes |
|---|---|---|---|
| Power | Battery + constant | Red / Orange | Orange often fused B+ |
| Power | Ground | Black | |
| Power | Ignition switched +12V | Pink | |
| Power | Accessory +12V | Orange | |
| Power | Starter signal (S terminal) | Purple/White | |
| Charging | Alternator output (BAT) | Red / Orange | |
| Charging | Alternator field / sense | Brown | |
| Ignition | HEI module ignition feed | Pink | |
| Ignition | Coil tach terminal | White | Points & HEI era |
| Ignition | Knock sensor signal | Dk Blue/White | |
| Fuel | Fuel pump relay power | Gray | |
| Fuel | Fuel pump ground | Black | |
| Fuel | Fuel level sender | Purple | |
| Sensors | Coolant temp sensor (ECT) | Yellow / Yellow/Black | |
| Sensors | O2 sensor signal | Purple | TBI/TPI era |
| Sensors | MAP sensor signal | Lt Blue | |
| Sensors | TPS signal | Dk Blue | |
| Sensors | IAT sensor signal | Tan/Black | |
| Lights | High beam | Lt Green | |
| Lights | Low beam | Tan | |
| Lights | Brake light switch | Lt Green | |
| Lights | Left turn / stop rear | Yellow | |
| Lights | Right turn / stop rear | Dk Green | |
| Lights | Reverse lights | Lt Blue | |
| Lights | Park / tail lights | Brown | |
| Audio | Radio constant +12V | Orange | |
| Audio | Radio ignition +12V | Yellow | |
| Audio | Radio ground | Black | |
| Audio | Radio illumination | Gray | |
| Audio | Front left speaker (+) | Tan/White | |
| Audio | Front left speaker (−) | Gray/White | |
| Audio | Front right speaker (+) | Lt Green/White | |
| Audio | Front right speaker (−) | Dk Green/White | |
| Audio | Rear left speaker (+) | Brown/White | |
| Audio | Rear right speaker (+) | Yellow/White |
35 results
Always verify with a wiring diagram for your specific year, make, and model. Wire colors vary by year, trim level, and production run. This reference covers common conventions — never trust color alone when tracing safety-critical circuits (brakes, fuel, ignition).