Copied this from a quick search on glowplugs & ohms.

"Any GP that doesn't read about 0.7 ohms is suspect. Do the 12V test (across battery terminals) on any GP that doesn't read 0.7 ohms. Replace any bad GP."

The search had 4-5 threads regarding 240D glowplugs and I think I saw how they were testing the relay.

From what I have read, you need to know if your glowplug indicator light on the dash appears to be cycling correctly.

__________________
Steve
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