Relays SG+
All the relays are 12 Vdc relays. The relays on the microprocessor PC board are interchangeable. The relays mounted on the inside of the control box are interchangeable. The relays on the microprocessor PC board are not interchangeable with the relays mounted on the inside of the control box. Test a relay by interchanging it with a known good relay.
Ignition Relay
The Ignition relay (RL1) is located on the PC board. It supplies power to the ECU. The RL1 LED on the PC board will light up when the Ignition relay is energized.
Run Relay
The Run relay (RL2) is located on the PC board. It supplies power to the ECU. The RL2 LED on the PC board will light up when the Run relay is energized.
Preheat Relay
The preheat relay is mounted on the inside of the engine compartment. It supplies power to the glow plugs. If the preheat relay fails a P code will be generated in the ECU and the controller will display a message.
| 1. | Spare Relay (If Installed) | 4. | Ignition Relay (RL1) |
| 2. | Fuel Pump Relay | 5. | PC Board |
| 3. | Run Relay (RL2) | 6. | ECU Fuses |