Glow Plug Heater: Efficient & Reliable Heating

Hello.

I have a Golf IV (AJM engine) manufactured in 2001, which has the three glow plugs located in the water flange.

To my knowledge, the glow plugs should be activated via the relay when the intake air temperature is below 5°C and the coolant temperature is below 50°C.

I just checked, with an outside temperature of 0°C and a cold engine, whether electricity is actually reaching the glow plugs (using a test lamp). However, the lamp is not lighting up.

Here's what I've already tried before.

"The intake air temperature readings, obtained using VAG-COM when the engine is cold, are quite consistent in measuring block 7. A glow plug diagnosis was performed, and a lamp was connected to the terminals --> the lamp flashes intermittently. Glow plugs were tested using a 40W lamp."
checked --> also OK.

Are there any other parameters that the control unit takes into account besides the temperatures and the data contained in measurement block 16?

I've read through some of the topics here, but I haven't found anything that quite fits.

Thank you.

Yes.

The speed or terminal DF (corresponds to the load of the alternator).

If the engine is idling roughly, the alternator may not be able to provide enough power, which can cause certain components to shut down. You probably checked the voltage at idle, right?

Okay, ma'am, please have her press the pedal, keeping the engine speed at a minimum of 1500 RPM (the engine, not the woman), and then take another measurement.

m;

Thank you.

I'm going to try that right away.

What percentage value is displayed in the measuring block, column 16, when the alternator is under load?

I just tried it.

Laptop connected.

Measurement block 16: After 10 seconds of motor operation, all bits switched to 0 (column 2).

Last signal approximately 55% (column 1).
Column 3: Relay Control 00.

Engine speed increased to 2000 RPM, daytime running lights turned off.

Column 3, Display 01: (Relay for low heating power engaged --> Lamp illuminates).

Column 1: Load signal, approximately 30%.