Glow Plugs
Glow plugs heat the combustion chambers to help the engine start in cold weather. The glow plugs are energized by the ECU (Engine Control Unit) through the glow relay during preheat, just before the engine is started.
The ECU controls glow plug operation in three phases based on Engine Coolant Temperature and Barometric Pressure.
| State of Operation | Voltage at Glow Plugs | Coolant Temperature | Time Limit |
|---|---|---|---|
| Pre-Heat 100% Boost (Engine not Running) | 12 Volts | Less than 68 F (20 C) | 0-1.9 Seconds |
| Pre Heat Maintain (Engine not Running) | 5 Volts | Less than 77 F (25 C) | 1-8 Seconds |
| Post Heat (Engine Running) | 4 Volts | Less than 140 F (60 C) | Up to 900 Seconds |
- Notice
- Equipment Damage
- Applying battery voltage to glow plugs for extended durations can damage the glow plugs.
The glow relay detects electrical defects in the relay itself and in individual glow plugs. It provides diagnostic feedback to the ECU, which communicates with the microprocessor to record Alarm Code 811 Glow Plug Circuit Error.
Use EXXODiag to view the DTCs (Diagnostic Trouble Codes) and diagnose the problem. Refer to Service Procedure A60A in the SR-4 Trailer Multi-Temp Diagnostic Manual (TK 55788-2-OD) for more information about using the Peugeot EXXODiag Diagnostic Tool to connect to the ECU.