Convertible Top Circuit Breaker

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Hello Everyone...it's been a while since I've posted on the forum!
Question I have is, can the 20 A circuit breaker go bad? I mean my top was working fine before and after I bled the system (had to run it up and down at least 15 times to get all the air out) and to get a new top installed soon. I went to the top shop and as soon as I tried to demonstrate that my top is working it wasn't, LOL.
Now my top won't move with the CB attached to the positive side of the starter solenoid and the CB only makes a strange clicking sound. Top pump has good ground. Can the CB be tested and if so, how? If I attach the lead directly to the + side of the solenoid (without using CB) my top works fine.
I was able to find a NOS Ford in the box CB, installed that and it is just clicking sounds like my old one. I'm stumped!

Any help and or advice is greatly appreciated, thanks.

Have a Great and Save 4th of July
 
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Yes, breakers can fail. It sounds like you are testing it (sort of) - when you activate the top switch, it draws current through the breaker, the current is too much for the breaker and it trips. The question is, is the breaker tripping too soon or is the motor drawing more current now.

An ammeter is the only way to really know for sure. Depending on the meter type you have, you will need to either put the meter in series with the breaker, or add a test piece to the circuit in series with the breaker. The test piece is actually a bit of metal with known resistance. The meter indirectly measures current by measuring the voltage drop across the test piece and does some math (V/I=R). Or, if you don't have an ammeter, you can get a big honking 5 ohm 100 watt resistor and do your own math.
 
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Well guys...you're not going to believe this. Hooked up my battery and NO clicking from the CB. Activated my top switch and everything runs smoothly, the gremlin is gone!

Thanks though for the advice!
 
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My all time favorite vehicle is our 1969 Shelby GT500
If you ever want to do an amperage draw test on the vert I have a YouTube video that shows how to do it using a VAT-40 inductive ammeter (a hand held inductive ammeter will work just as well). And, yes Circuit Breakers can and do go bad. When they fail intermittently hey can be difficult to diagnose. They are fairly inexpensive. If I were you I would just replace it before it begins to give grief again. My two cents.

If you do not yet have a hand held inductive ammeter I got mine via Amazon at:



My YouTube video re: testing amperage draw on vert Mustangs is at:

 
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Well guys...you're not going to believe this. Hooked up my battery and NO clicking from the CB. Activated my top switch and everything runs smoothly, the gremlin is gone!

Thanks though for the advice!
No, the gremlin is waiting for the time you are out on a tour in the middle of the countryside with the top down and it starts bucketing down rain.
 
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Mine failed during a brief rain storm here in Arizona. It was the ground that was causing the problem. But yes, the gremlins show up at the worse time. It's like when you are at the gas station and someone comes over and admires your car, you chat a bit and then you go to start it and it either won't start or takes a lot of cranking while they are watching!
 
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