2.25 Diesel glow plugs and ballast resistor

Webley1991 said:

Am I right that with modern 12v glow plugs that the ballast resistor is redundant? These are the plugs which only have a wire running into the end plug from the resistor. I believe these are wired in parallel with the block being the earth. Am I right here?

The ballast resistor was connected up when I first bought the vehicle, but I was told that it had modern glow plugs fitted.

The glow plug light also used to be very dim to the point that it couldn't be seen in daylight. I was also told that this was due to the modern plugs.

Does this sound correct? I just want to make sure I know what I'm doing before starting re-connecting the wiring, which is still quite a way off yet.

Thanks for any replies.

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dag019 said:

It depends on what modern glow plugs you have. I ordered the complete kit (plugs and wiring) to convert from the old style to the modern ones and the instructions say to still use the ballast resistor. Although on the research from forums that I did before ordering them said you could do either.
If the ballast resistor was connected up before and everything worked as it should I would reconnect it the same way.

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Webley1991 said:

Thanks for the replies.

This is how it was connected up before. Sorry for the bad quality photo, I cropped it out of a photo of the engine bay I took on my old phone.

The red wire runs to the plugs. The description of how the lamp works with the resistance would explain the extra two wires coming off it.

Does the resistor coil get hot during normal operation?

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