Mk1 fuse blown

[tonymor]

My mk1 suddenly had no indicators , rev counter, oil and water gauges.
Found a 10a fuse blown in box above drivers foot . Replaced all well until I drove only a few yards and its blown again?
Any suggestions how to fix please?

[Oldandslow]

Mine does or did this on occasion. Every time has been whilst driving in the rain. In fact since the car is now fair weather only it hasn't happened in at least 5 years. Back in the day it was rumoured to be something to do with the alternator regulator but I've no info to back that up. Can't say if it was dampness or additional load from wipers and lights. Might be some old threads here or on MX5oc.

Never got as far as changing the alternator just kept a ready supply of fuses and got quick at changing them.

[tonymor]

Have you found and cured the cause as yet?

[Oldandslow]

Sorry but no. Since it stopped happening it slipped down the list of priorities and it never really got investigated properly.

[tonymor]

Oddly enough I drove mine last evening for a short distance and all seemed well so mystery continues?