An electrical fault is draining the battery if my car is not used regularly - how do I find it?

An electrical fault is draining the battery if my car is not used regularly. What fault could this be and what should I do to rectify the fault?

Asked on 27 November 2017 by amjid khan

Answered by Honest John
It might be the interior light delay switch that can remain live after the light has gone out. Or might be the radio/Bluetooth. If it's the latter, install a separate switch into the radio power lead so you can switch it off entirely separately from the ignition or the radio itself.
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