Current drain source. ignition switch?

[hangit]

My 240D suddenly has developed an intermittent current drain. Battery tests fine under load, alternator charging to 14.5V at battery. Ammeter registers 0.01MA at battery with only clock running, but spiked one time. I heard a click when re-connecting the Neg battery cable which sounded like the glowplug relay. Disassembled the relay, no corrosion. I could not duplicate the spike. Can the ignition switch be causing this intermittent problem? Thanks for any help in diagnosing the problem.

John