cub cadet lt1045

jerry1980

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The fuse next to the battery blows after about 5 seconds or less of running. The fuse will not blow unless the mower is running, in other words if I just turn the key to run with out starting it doesnt blow. Using a Power Probe which has a 15A circut breaker and can be used to apply power to the circut. While monitoring the volt meter on the probe it goes over 15 volts when the breaker trips. It appears to me that the charging voltage is too high?? I put a new (aftermarket) voltage regulator on it and the problem still exist. If I unplug the regulator the mower continues to run and the fuse doesnt blow. Any ideas or common issues? Is the new regulator bad or could a bad cell in the battery cause this?

Thanks Jerry
 

Rivets

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Two things to check. Most fuses blow due to a short circuit. Check every wire and connect you can find. Main areas that have me thinking are around the key switch and solenoid. Does it blow while the engine is running or while you are trying to start it? This makes a difference where to check. Please give the CC model number.
 

Lawnranger

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The fuse next to the battery blows after about 5 seconds or less of running. The fuse will not blow unless the mower is running, in other words if I just turn the key to run with out starting it doesnt blow. Using a Power Probe which has a 15A circut breaker and can be used to apply power to the circut. While monitoring the volt meter on the probe it goes over 15 volts when the breaker trips. It appears to me that the charging voltage is too high?? I put a new (aftermarket) voltage regulator on it and the problem still exist. If I unplug the regulator the mower continues to run and the fuse doesnt blow. Any ideas or common issues? Is the new regulator bad or could a bad cell in the battery cause this?

Thanks Jerry

I had almost the identical case come in to my shop and I was going to replace the voltage regulator since when I unplugged it the problem went away but the regulator tested good. I finally found the problem and it was the small red wire going to the solenoid that intermittently shorted to ground. I traced the whole wire harness and found this red wire was rubbed through to ground and intermittently shorting. Now I fully know that this wire only has power on it when the key is turned to start but after I repaired the insulation on the wire the problem has not happened again in months. Go figure.

Finding this type of problem can be time consuming but if I were you I'd start at the solenoid and remove all the wires from the wiring harness and check each and every one of them for rubbed through insulation. The place where I found the problem was on the left side of the machine aft of the deck where the harness is wire-tied to the frame and makes some bends. Your machine is very similar to the one I had and I wonder if this is a design flaw.

Good luck and I hope this information helps you find the problem. By the way, when you do ultimately fix your mower, please come back to this thread and tell us what the problem was so we can help others with the same or similar problem in the future.
 

jerry1980

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Two things to check. Most fuses blow due to a short circuit. Check every wire and connect you can find. Main areas that have me thinking are around the key switch and solenoid. Does it blow while the engine is running or while you are trying to start it? This makes a difference where to check. Please give the CC model number.

The fuse will not blow while cranking, only once it has started and began to idle. Cub Cadet LT1045 Model# 621-879 13AX11CH756. Up to this point I have checked pretty carefully for chaffed wires and bad connections, but I do not see anything. I am pretty confident that the issue has to do with charging voltage. It will steadily increase to over 15 volts close to 16 volts and thats when the breaker in my probe will trip. I also tried a different battery with no change.
 

jerry1980

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I had almost the identical case come in to my shop and I was going to replace the voltage regulator since when I unplugged it the problem went away but the regulator tested good. I finally found the problem and it was the small red wire going to the solenoid that intermittently shorted to ground. I traced the whole wire harness and found this red wire was rubbed through to ground and intermittently shorting. Now I fully know that this wire only has power on it when the key is turned to start but after I repaired the insulation on the wire the problem has not happened again in months. Go figure.

Finding this type of problem can be time consuming but if I were you I'd start at the solenoid and remove all the wires from the wiring harness and check each and every one of them for rubbed through insulation. The place where I found the problem was on the left side of the machine aft of the deck where the harness is wire-tied to the frame and makes some bends. Your machine is very similar to the one I had and I wonder if this is a design flaw.

Good luck and I hope this information helps you find the problem. By the way, when you do ultimately fix your mower, please come back to this thread and tell us what the problem was so we can help others with the same or similar problem in the future.

Do you recall if the tractor you had was overcharging? I havent had time to pull the harness out or apart. But a good visual inspection and lots of wiggle testing have not revealed any issues such as a short. My thought is that a shorted wire would trip the fuse instantly or for instance when a certain manuver pinch'es or rubs the wire. This mower will run for several seconds and it appears that as the charging voltage increases it will trip the fuse and shut off. I am begining to think that possibly the new regulator is no good. Otherwise disconnecting the regulator should make no difference if the short is still there right??
 

Lawnranger

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Do you recall if the tractor you had was overcharging? I havent had time to pull the harness out or apart. But a good visual inspection and lots of wiggle testing have not revealed any issues such as a short. My thought is that a shorted wire would trip the fuse instantly or for instance when a certain manuver pinch'es or rubs the wire. This mower will run for several seconds and it appears that as the charging voltage increases it will trip the fuse and shut off. I am begining to think that possibly the new regulator is no good. Otherwise disconnecting the regulator should make no difference if the short is still there right??

I don't recall if the tractor was overcharging or not, sorry. This one did the same thing by running for a few seconds or up to 20 seconds and then the fuse blew. I know what you mean by looking in the charging circuit because of the higher charging voltage but this one was doing almost the exact same thing and I thought the same as you but it ended up being that wire I described in my earlier post. I sure don't want to send you on a wild goose chase but you may save yourself some time and money by physically inspecting every inch of that wire and all the wires in that part of the harness.

Another helpful tool I used on this case was a short finder made by Snap-On which has a circuit breaker in it and that made it so I didn't have to replace the fuse to test it every time. You can get just a 10 or 15 amp circuit breaker from Autozone to use for testing purposes and maybe save yourself some money in blown fuses.

Another thought would be to check the red wire from the fuse holder all the way back in the harness, too. If that wire is intermittently shorted to ground, it could cause the same problem.
 

jerry1980

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I don't recall if the tractor was overcharging or not, sorry. This one did the same thing by running for a few seconds or up to 20 seconds and then the fuse blew. I know what you mean by looking in the charging circuit because of the higher charging voltage but this one was doing almost the exact same thing and I thought the same as you but it ended up being that wire I described in my earlier post. I sure don't want to send you on a wild goose chase but you may save yourself some time and money by physically inspecting every inch of that wire and all the wires in that part of the harness.

Another helpful tool I used on this case was a short finder made by Snap-On which has a circuit breaker in it and that made it so I didn't have to replace the fuse to test it every time. You can get just a 10 or 15 amp circuit breaker from Autozone to use for testing purposes and maybe save yourself some money in blown fuses.

Another thought would be to check the red wire from the fuse holder all the way back in the harness, too. If that wire is intermittently shorted to ground, it could cause the same problem.

Ok thanks for taking the time to respond on a holiday. I will surely look closer there. I am using the power probeIII which has a circut breaker also, my all time favorite tool. PP319FTC Power Probe III ....?Powers up Components!?
 

Rivets

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According to the Kohler troubleshooting guide a voltage reading of over 14.7 is an indication of a faulty regulator/rectifier. I'm assuming you have a 15amp system.
 

Lawnranger

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I took my voltage regulator to the Kohler dealer and he tested it for free and said it was good. You may want to do the same just to be sure. Rivets pointed out a valid piece of information and I'd sure test the system according to the manual, however when I tested the one I had in the charging system was working properly if I recall correctly.
 
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