Dave928S

If you had a heat failure of the relay I'd expect a permanent failure of coil or contacts because of the extreme heat operating environment ... which would blow fuses and keep blowing them. The heat shouldn't have any significant effect on current in the coil circuit ... the control circuit either conducts normally or it gets cooked .. permanently.

I'd be leaning towards the explanation being the the cheap nature of the device, and even though its running below spec, maybe you got more of a fuse melt, like Alan referred to, than a fuse blow. I wouldn't be surprised if you find that cleaning all contacts thoroughly and putting in a new fuse might mean you don't experience the issue again.

soupcan

Dave928S

^^^ A picture's worth a thousand words.

Tampa 928s

Thought those were rated for 10-amps I see 20-amp fuses on both!

Soupcan how did you tilt your radiator forward and secure it so it is tight?

Alan

What you need to worry about is the wiring on the back of the CE to that fuse as well as the Add-A-Fuse itself. You shoudl assume as an absolute limit 20A on any CE slot so 10A fuses would be the max anyway (a total of 20A max) and limited further by the Add-A-Fuse specs.

I generally like these a lot - for small accessories - great way to add a radar detector for example...

I would not typically (nor does Porsche) include fuses for relay coils - coils winding wires are always a weak link - and act like a fuse themselves.

Something else is going on if your coil only circuit is blowing a 10A fuse - investigate - it is not the coils... they will burn out well below this...

Alan

Tampa 928s

The add a fuse is out of the picture and fuse has not blown, good to know about the coil opening before the fuse. The rating of the relay is 189 degrees I measured 159 degrees after a 10 mile drive on the firewall where they are attached. I will check my wiring the failure of the fuse was while in a drive through after a 10 mile drive.