Why is the glow plug light not working on my Mk4 Golf?

The problem then was the main ecu relay (provides power to the ecu) failed and didn’t power up the ecu. A lack of glow plug light was always a giveaway. It was relay 109 which was faulty back then (on the Mk4 Golf platform etc.) but I’m not sure which relay it would be now. Seriously? You need to ask? That’s a stupid question!

Why are the glow plugs on my Audi not starting?

If the glow plugs lights are flashing & it’s not starting it’s usually a sign that the injectors &/or loom is faulty (bizarrely), is it a PD170? And what is the exact code that’s being thrown up?

Why does my glow plug light up when I start the engine?

If the test light lights up, the plug is receiving power. Evaluate whether or not the relay is able to supply the power required to start the diesel engine by testing the ohms of the circuit with an ohmmeter. A working relay will produce between 50 and 120 ohms. If the circuit is producing less than 50 ohms, the relay is suspect.

How to troubleshoot a problem with a glow plug?

1 Evaluate which parts of the glow plug system are easily accessible. Start with the easiest and work your way to the hardest. 2 Find the wire from the glow plug temperature relay. If the wire is disconnected, reconnect it. 3 Observe if the glow plugs are getting the power they require by connecting a test light to the plug.

If the glow plugs lights are flashing & it’s not starting it’s usually a sign that the injectors &/or loom is faulty (bizarrely), is it a PD170? And what is the exact code that’s being thrown up?

The problem then was the main ecu relay (provides power to the ecu) failed and didn’t power up the ecu. A lack of glow plug light was always a giveaway. It was relay 109 which was faulty back then (on the Mk4 Golf platform etc.) but I’m not sure which relay it would be now. Seriously? You need to ask? That’s a stupid question!

If the test light lights up, the plug is receiving power. Evaluate whether or not the relay is able to supply the power required to start the diesel engine by testing the ohms of the circuit with an ohmmeter. A working relay will produce between 50 and 120 ohms. If the circuit is producing less than 50 ohms, the relay is suspect.