Could the temperature sensor (for the relay?)
be out of range? I believe there is a sensor
on the block near the plugs.

Could that be why the light does not come on
when it is warm (sensor out of range)?

Could it also mean that the plugs are not
warming up enough when it is colder?

I'm also not clear on whether there is a
direct connection between the plugs "glowing"
and the dashlight illuminating. From your reply,
it sounds like there is not a connection but I
would like to understand it better.

Jeff / '82 240D