Ground Circuits
- Turn ignition off. Using DVOM in ohmmeter mode, backprobe each ECU ground terminal. See ECU GROUND TERMINAL IDENTIFICATION table. Resistance should be zero ohms. If resistance is not close to zero ohms, repair open to ground.
- Start engine. With DVOM in voltmeter mode, backprobe each ground terminal. Voltage should be less than one volt. If voltage is greater than one volt, check for open, corrosion, or loose connection on ground lead.
ECU GROUND TERMINAL IDENTIFICATION
| Application | Wire Color | |
|---|---|---|
| Impreza | ||
| Terminal A14 | Black | |
| Terminal A15 | Black/Yellow | |
| Terminal A25 | Black/Brown | |
| Terminal B11 | Red/Green | |
| Terminal B22 | Black/Red | |
| Justy | ||
| Terminal A10 | Black/Red | |
| Terminal B1 | Black/Green | |
| Terminal B2 | Black/Green | |
| Terminal C1 | Black/Red | |
| Terminal C13 | Black | |
| Terminal C26 | Black | |
| Legacy | ||
| Terminal A11 | Black/Red | |
| Terminal A21 | Red/Green | |
| Terminal A22 | Black/Red | |
| Terminal D14 | Black/White | |
| Terminal D15 | Black | |
| Terminal D24 | Black/Yellow | |
| Terminal D25 | Black/Yellow | |
| Loyale | ||
| Terminal B30 | Brown | |
| Terminal B42 | Brown | |
| Terminal C44 | Brown | |
| Terminal C51 | Black | |
| SVX | ||
| Terminal A11 | Black/Red | |
| Terminal A22 | Black/Blue | |
| Terminal D15 | Black | |
| Terminal D14 | Black/White | |
| Terminal D24 | Blue/Black | |
| Terminal D25 | Black/Yellow | |