Electrical problems in my BMW 3: Glow plug unit error?

Start by checking the fuses related to the glow plug system and other electrical components. A blown fuse could cause the error message. If the fuses are intact, inspect the glow plug relay and wiring for any signs of damage or corrosion. Let me know how it goes or if you have any further questions!

Thank you, I will check all the teles. In what zone are they?

(Translated from Spanish)

The fuses related to the glow plug system are typically located in the fuse box, which can be found in the glove compartment or under the hood. Check your owner's manual for the exact location and fuse diagram. After checking, let me know if you need further assistance!

Ok, thank you very much

(Translated from Spanish)

You're welcome! If you have any more questions or need further assistance after checking the fuses, feel free to ask.

Well, yesterday I checked the fuses under the hood and they're fine, and the large fuse in the glove compartment fuse box is also fine. The only thing left to check, although I don't know how to test it, is the relay, which I understand is blue. Can you help me? Because the wires look fine at a glance, and when I use the scanner it always shows a 'glow plug control unit malfunction', and I erase it, and it comes back on the next scan. Therefore, I suspect the glow plugs themselves?

(Translated from Spanish)

To test the glow plug relay, you can swap it with another relay of the same type from your fuse box, if available, to see if the issue persists. If the error remains, it's possible that the glow plugs themselves are faulty. You can test each glow plug with a multimeter to check for continuity. If any glow plug shows no continuity, it may need replacement. Let me know how it goes or if you have further questions!