Good Evening
My 1970 E Type OTS keeps blowing the fuse for the dash/instruments lights. It’s getting a little inconvenient monitoring the gauges with a flashlight ! Anybody have experience with this?
Many Thanks / Jack
One thing you might find useful while trying to find the cause (which may be a short in the wiring or switch) is to use an old headlamp in series in place of the fuse. The headlamp offers an observable load that is, in effect, a reusable fuse.
The headlamp will light up when the dash lights are turned on but will shine very brightly if there is a dead short. A big ammeter can do the same thing but a spare headlamp is usually easier to source. I always save an old lamp just for this purpose.
You can also use a small lamp (like a taillight) for this.
sounds like you have a short. my suggestion is to unhook all the wires from the load side of the fuse first. then touch each wire to the fuse at a time so you can tell which line has the short. then keep undoing all the lights etc. then attach them back one at a time until you blow the fuse.
The other option is to use a DMV (digital multi meter) to see if one of the wires goes to earth.
Mine shorted or once because one of the metal lamp housings for the tach fell out. If the tip hits metal…poof
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yes better idea to use DVM than a pack of fuses:)
That’s what I had. Speedo rather than tacho, but the same cause. I think the fuse also protects the side lights, hence no lights at the rear when it blows.
Of course this only happens when you need to drive at night. It’s the law.
Yup and that’s how I found out one night. Some kind soul followed me for a bit to tell me my tails were out. I’ve since put some heat shrink around the hot contacts so if something falls out it won’t short.
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Click on the hyperlink to this post I did a few weeks ago.