The owner had used his own scanner unit to read the fault code of P037D on this 2006 BMW 530 diesel, indicating that the glow plug circuit had a malfunction. Armed with this information, my first step was to check the glow plugs.

The job time on replacing the glow plugs on this BMW is 1.5 hours, and this includes removing the inlet manifold. Once the manifold is out of the way ,the glow plugs are very accessible and easy to work on. Using a meter to check the ohm reading of the glow plugs showed no faults, so I carried out a continuity test on the wires between the glow plugs and the control unit.

Again nothing was showing up as indicating a problem. Only when I looked carefully into the caps that secure onto the glow plug tops, did I discover that while the lead on number two glow plug appeared to be ok, it was not making a good contact.

A little adjustment and cleaning was needed to the cap. After rechecking, all was well. With the inlet manifold back in place and the engine back up and running, I could confirm that the code had cleared and all was well.

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