Need Help finding short

chope97

chope97

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I have posted about this before my 73a keeps blowing fuses on number 11, which is temp gauge, fuel gauge, auto choke solenoids, tach, oil pressure warning light. I unplugged just about all of these devices and it still blows the fuse as soon as I start the car. The car will start but will not idle. Are there other items on that circuit that are not listed on the lower dash door legend. Is there some other way to check for a short? I noticed that the wires to the auto choke come from a device located on the back of the brake booster could the problem be in this device? I have not driven my car this year
 

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I take it you can turn the ignition on and nothing happens but only if you start it the fuse blows?
If you disconnect existing wires and feed the idle shut off solenoids with a fused jumper (if you have them) will it idle?
Make a "map" of existing connections/wire colors on the suspect relay, compare to wiring diagram, and see if disconnecting makes a difference to fuse.
You may want to get yourself a circuit breaker and a test light and save the fuses.
Also follow the wires to the carbs and see if no crossed connections or shorts to ground.
 
2000CS said:
I take it you can turn the ignition on and nothing happens but only if you start it the fuse blows?
If you disconnect existing wires and feed the idle shut off solenoids with a fused jumper (if you have them) will it idle?
Make a "map" of existing connections/wire colors on the suspect relay, compare to wiring diagram, and see if disconnecting makes a difference to fuse.
You may want to get yourself a circuit breaker and a test light and save the fuses.
Also follow the wires to the carbs and see if no crossed connections or shorts to ground.
Click to expand...
Thank you, I finally found the problem this box which seems to be unique to 1973 (I have a 71 and 74 and neither has this box) controls power going to the the carb idle solenoids. When I unplugged it the fuse stopped blowing. It receives it power from fuse 11 via a green wire with white stripe. I am going to by pass it. I used about 20 white fuses trying to figure this problem out. I unplugged everything on the circuit but did not know what this box was until I started tracing the green/white stripe wire to it. I purchased two short finder devices but because it is so hard following wires under the dash they were useless. I even took the fuse block a loose to look on the back side to see if there were any obvious problems. I looked at the book schematic and that is when I saw that things on this circuit get feed by a green/wire strip wire. Now to put everything back together and while I am there clean and fix stuff under the dash.
 
Disconnect the wire to solenoids from the relay and check to make sure it is the relay that's giving rise to the problem and not the idle cut off solenoids/wiring.
 
2000CS said:
I take it you can turn the ignition on and nothing happens but only if you start it the fuse blows?
If you disconnect existing wires and feed the idle shut off solenoids with a fused jumper (if you have them) will it idle?
Make a "map" of existing connections/wire colors on the suspect relay, compare to wiring diagram, and see if disconnecting makes a difference to fuse.
You may want to get yourself a circuit breaker and a test light and save the fuses.
Also follow the wires to the carbs and see if no crossed connections or shorts to ground.
Click to expand...
To answer your earlier question I did not have to start the car just turn it to the on position and the fuse would pop, the green white wire going to the solenoid is in bad condition , when i move it it broke, so we will see if it is just the wire after I fix it
 
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