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Wiring Harness Issues -- Any Thoughts?

Bill_Reid

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I have been installing a new wiring harness in my '60 Sprite as part of the almost completed restoration. You may recall that I posted an earlier query regarding the installation. I received some good advice. As a result, I went back through the harness, checked every connection. I discovered a couple of connections that were not right, as well as a defective flasher. Based on my friend Charlie's advice about making sure that all grounds were well connected, I rechecked the grounds and found some problems. I then decided to rework the grounds. I installed two bolts through the firewall, making sure that there was lots of shiny metal in contact with the bolts. I replaced all the one wire bulb holders with two wire holders and took the resulting ground wires back to one of the bolts. I then extended all the other ground wires to the other bolt. All of the ground wires have crimped and soldered connectors protected with heat shrink tubing on the end which is connected to the grounded bolts.

Ok, all is well..Right? Nope! The lights, turn signals, wipers all work, but, with the lights on, when I engage the dip switch, the inline 10 amp fuse blows...I am sure the dip switch is connected correctly, But something's not right. Any thoughts on what to check/do now? FYI the tach is converted to electric and there is a Flamethrower distributor, so these are connected into the system. I believe these are connected correctly, but...

Oh, and I did ground the white with black wire from the harness in the engine bay since the distributor comes with its' own wires.

One other thing..the wiring chart shows a white wire running from the combination ignition/lighting switch to the cigar lighter. The other side of the cigar lighter has a red/white wire running to the panel light switch. I do not have a cigar lighter. Should I run a wire from the panel light switch directly to the combo switch?

Many thanks in advance for any thoughts/ideas!!
 
I just had a thought..Is it possible that the 10 amp fuse I have on the brown wire from the harness to the battery is too small?
 
yes.
 
Just be careful remember not to let the smoke out of the harness. You're getting close. GO SLOW!!!
 
Bill,

I would check with an ohm meter and see which terminal is picking up a ground. Check with the wires disconnected first to make sure none of the terminals are touching ground or that the switch isn't shorted out. Next, I would check the terminals to the headlight to be sure a ground wire has been misplaced into the high or low beam. Next, I would go to the combo ignition/light switch. Check the switch for an internal short and/or that one of those open terminals aren't touching ground and/or wired incorrectly. If all that checks out, time to trace the individual headlamp wires for a ground source where it doesn't belong. It's all about process of elimination. Then slap your forehead when you find the mistake and say "d'oh!"...:congratulatory:
 
Thanks, Gerard......I will go to work on it!
 
Being in Oriental I assume you know Charlie O. He will be a wealth of information if you have not already discussed this with him.

EDIT: You also said you had grounded the white/black wire since you are not using the stock ignition, then you went on to say that you have an electronic tach fitted. There is no need to earth the white/black wire if it is not connected to anything. In particular, make sure if you have earthed it that you did not leave the other end connected to the coil. If you did... this makes a permanent kill switch. Disconnecting both ends of the white/black is preferable to earthing one end.

Later (much later) BMC/BL cars pulled a second white/black wire from the coil (-) terminal to supply signals to the Smiths RVC voltage sensing tachs. I assume your car still has its original wiring harness and this would not apply to you car.
 
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