Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Fuses - RH Main Beam

A few weeks ago my 2011 Roadster Sport stopped running after hitting a large pothole. Thought it might be the inertia switch but no and then did a cursory bit of fault investigation on the side of a busy and narrow country road but with no luck. We ended up being recovered to Williams for deeper investigation. Transpired it was the fuse to parts of the dashboard including the immobiliser but I was sure I had checked the fuses on the roadside ......

Roll forward a month and the RH main beam stopped working during a long and often bumpy journey. So I thought bulb and therefore a good opportunity to swap older bulbs for Night Breaker or something similar. Purchased a pair of Philips RacingVision GT200s on Saturday from Amazon (Saturday evening) and they arrived on Sunday afternoon (amazing delivery performance) so had a go at fitting them yesterday. I changed the RH bulb first and then checked the lights again and the same fault remained. So perhaps a defective new bulb or something else? Fortunately I looked at the something else first before changing the bulb for a second time and started with the fuse box. Again nothing blown but removing and replacing the small 10A fuse for RH main beam appears to have fixed the problem. As an aside, multimeter on the old bulb demonstrated that it was not blown after all.

Is this a feature/issue that others have experienced or might I have a problem with my fuse box?

Sounds like dodgy fuses or indeed a loose / corroded connection somewhere.

Sounds like some corrosion has crept into the fuse holders to me?

Thanks both - I thought that too so will pull the fuses and spray very carefully with contact cleaner.

I would agree adding that as I believe most are located under the dash there may be a leak allowing ingress of water from the inside of windscreen. I understand some folk attach a large flap of leather over the top of dash electrics to catch any such leaks and drip harmlessly away.

I think some Mogs have problems with the blade fuses as the holder often has brass contacts & the fuse tangs are perhaps just steel coated in tin so they don't bend too easily, this could be the cause of some bi-metallic corrosion, if you pull the fuse & it's a bit white & crusty, there's your cause

After a poke round with the fuses today I found I hadn’t solved the problem (poor diagnosis on my part) so still no main beam on the right hand side. Power gets to the fuse when main beam selected and the blue main beam light comes on when the fuse is in. But no main beam power to the bulb holder so must be a wiring problem. Dipped beans and sidelight are fine. Bit beyond me I fear so off to an auto electrician next week. Anyone know of a good one in the Bath/Westbury area (and ones to avoid if there are any)?

I suspect it'll be one of the dreaded bullet connectors under the front wings then

If the side light also doesn't work it could be the earth as they share a common return

Sidelight and dipped beam both work ok and I’ve checked the earth. I guess I’ll seek out the bullet connector before a visit to the electrician.