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MG TD TF 1500 - Blown Fuse

While cleaning up the underbody and frame, I removed and repainted my horns. They were working when removed, but do not appear to be original to this car. They do not work after reinstallation. I checked and the 30A fuse for switched items (items that don't function if the ignition switch is in the off position) is blown. I replaced the fuse and it immediately blew again. If I reversed the electrical connection to either or both horns, would that cause the fuse issue? I have not changed anything else electrically. What else is on the switched circuit? Where should I look for the problem? Know that I am not a wiring guru.
Cheers,
Frank

Frank Bice

Frank, the horns are not connected to the circuit controlled by the fuse between the A3 & A4 terminals. They have their own fuse between the A1 & A2 terminals. I think you may need to find a guru to help you find the villain. Was everything fine before you worked on the horns? Bud
Bud Krueger

You are correct, Bud. I found a blown 30A fuse between the A1-A2 terminals, which is in the horn circuit. And yes, the horns worked prior to my removing them and reinstalling them. I may have switch the wiring connections inadvertently. Would that have blown the fuse? I intend to reverse the connections and see if that resolves the issue.
Cheers,
Frank
Frank Bice

Frank,
In theory it looks like it should not matter which way round you wire them - even if you crossed only one horn. Ground only comes into effect when you push the horn button, and the path would still be through the horn coil. Not a short.
Are the horns insulated form the chasse?
Try disconnecting both - then one at a time to see if it is a horn related?

Just a thought.

Oh yes - Buy some more fuses :)

Rod

R D Jones

It is not SUPPOSED to matter if the wires are reversed, as there is not supposed to be an internal ground connection. However, if they are not the correct horns or there is an internal short to ground, that could account for blowing the fuse.
Lew3

I once refurbished the Windtone horns on my TD and replaced the domed cover screw with nice new stainless ones but they were a quarter inch too long and shorted the horns to ground. Everything worked great with the covers off but as soon as I put them back on the fuse blew. Took some work to figure out what was going wrong.
John Quilter

This thread was discussed between 04/10/2015 and 05/10/2015

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