Astravan 02 reg - fan running on & draining power

In my experience, which is not universal, when strange faults occur, it is usually due to a number of faults coinciding, each one not really noticable on its own.

I have not tested the accuracy of automotive fuse ratings, but if they are anything like BS1362, then they will pass higher current than their rating.

A high resistance point, (a poor earth for example) acts as a current limiter, and prevents full volt drop across the consumer. A fault condition on one consumer where the current is limited by a bad connection, with a 'tolerant' fuse, could prevent another consumer operating correctly, especially if other consumers are running too.

I'm sure we have all seen strange faults caused by bad earths...

David

IME of over 40 years as an electrical tech, I've usually found the converse. Multiple failures are often *blamed*, but a single failure is more usually the cause.

Every fuse (or indeed circuit breaker) will require a current higher than its rating in order to operate. This value is known as its fusing factor.

For automotive fuses, which are essentially simple wire fuses, the factor will be around 2. IOW, a 10A fuse will require a fault current of 20A in order to open-circuit instantaneously.

Extremely unlikely in the case of the OP's fault however. There are well documented problems with Astra G PAS systems; he would be advised to go down that route first.

My personal all-time favourite is Escorts spluttering and dying when reverse gear is selected...

Chris

Yes, I have had that too.

Yes, different standards for different BS or EN ratings though.

Yes I know, but it will pass 15A for extended periods.

You have great skill in finding things with Google.

Last week, I there was a car behind that the front indicators come on when the driver pressed the brake pedal...

David