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reading schematic

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Woodie

Woodie

Jedi Warrior
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Good day guys, I am doing some research so I can fix an intermittant problem in the spring. Every so often my tach, wipers,heater fan, turnsignals and fuel guage stop working. The car keeps running. With help from others I believe the problem to be either with the fuse box (green wires/white wire) circuit or the green wire circuit under the dash above my left knee. When I look at the schematic NC9 I can trace the green wires from the fuse box to
1) the reverse light switch (my lights are not hooked up) and then
2)over to a point just right of #37. There is a small circle with 6 green wires in/out of it. These wires seem to go to the affected areas of my car. What is this type of connector. It is not the symbol for a bullet connector. I want to know what I am looking for when I lie upside down and start undoing DPO plastic tape on the loom.
 
I would bet that it is bad grounds or connections. Take em apart one at a time, clean and reinstall.
 
Unfortunately, my Haines manual shows at least 186,324 different wiring diagrams for later midgets. Some show different circuits for the heater fan, some show it to be common. It seems that the connection to the fuse block is the one thing common to all of these, so it probably is a problem with that connection.

In any case, problems like this are almost always with a connection somewhere, not an internal break in a wire--so it probably is best to leave major wiring-harness surgery as the last option. Cleaning and tightening all connections that could cause this problem will probably be the solution.
 
i would agree with that and only add that if you have had past wiring problems with heat or over current conditions you may have insulation damage inside the harness that can only be seen by removing the harness in certain areas. additionally, anywhere the harness is exposed to the street(like under the car, fenders, what not), there is always the possibility of insulation damage due to cuts, animals, heat, wear, fretting, as a result, if these areas are left exposed, they will corrode and act like high resistance resistors. the problem with that is you will read voltage at the terminals but as soon as the switch is flipped, the current flow will drop across this resistance and voltage will drop or disappear. therefore, i would also look at any wiring that is exposed, even in the trunk area. i would also try isolating suspect equipment. if you determ one part you may find everything starts working, then you have a more defined path to go down. good luck!
 
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That's an easy fix. Clean the fuse box terminals and the fuse.

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That's a good starting point.I started here and almost all the problems went away. /ubbthreads/images/graemlins/thumbsup.gif The rest were mostly dirty or loose connectors. /ubbthreads/images/graemlins/rolleyes.gif

Stuart. /ubbthreads/images/graemlins/cheers.gif
 
[ QUOTE ]
2)over to a point just right of #37. There is a small circle with 6 green wires in/out of it. These wires seem to go to the affected areas of my car. What is this type of connector. It is not the symbol for a bullet connector. I want to know what I am looking for when I lie upside down and start undoing DPO plastic tape on the loom.

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This is a splice point. If you look at the wiring harness, you'll see a "stub" sticking out of the tape an inch or two. All six of the wires shown on the diagram will be crimped together at this point. You should be able to see the green wires coming out of the harness.
 
Thanks Dan for answering my question. Now when I do clean all the connectors and recepticles I can also look for the stub and make sure all crimps there are good too. I will also be cleaning and checking connections and the rivets on the fuse box. There has been some DPO work on the loom under the dash, thats why I want to know what to look for. If its there or not, and I expect to spend an hour or two on my back in the spring checking and cleaning all the bullets. (HIOOO Lone Ranger)
 
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