I had the same problem with the Washer warning light staying ON and 'cured' the problem by removing the red 'relay' module. As one of the winter projects, I have been looking at that removed module, removed the thin layer of rubber sealant around the base and then removed the red cover to reveal the circuit board. An eyeglass inspection failed to identify any mechanical issues around the components, but did show a crack around one of the relay pins solder joints and showed poor continuity with a meter. I reflowed each of the pin solder joints, refitted the red cover and reinstalled it in the car and all has been good, no warning light for the past week. So I think I have cured my bad module. The joints I reflowed are in the yellow circled area:
BMIsml.JPG
I was sure the pin in question was 3rd from top which is Pin 2 of the module, which from the circuits shown on the Lotus Forums looks like a ground, however their (Esprit) car side wiring shows no connection to that pin which is confusing, and I think it confused them, shown on their sketches:
cct.JPG
And I don't think there are any Elan S2 wiring diagrams to confirm that pin 2 does/should connect to ground.
So bottom line is - I am fairly sure I fixed my bad relay by reflowing the solder joint on pin 2 of the washer warning relay/module. Would be interesting if anyone else with the same problem (that has been isolated to the module) has a look at those solder joints to see if this is common to their failed modules.
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