L3830 no power

[sula bob]

Tractor started fine yesterday then when I shut it off I couldn't get it to restart. The LCD display isn't coming on, no clicking noise from under the hood. I was able to get the LCD to come back on after turning the key on and off a whole bunch, but never long enough to get the tractor to turn over. The battery has 12.75 volts. There is 12.65 going to the ignition switch with the key off. With the key on it is putting out 16-17 volts, but the incoming power spikes. Not sure how it spikes, or what is causing it. I'm thinking it's a faulty ignition switch or a bad relay. Any ideas before I go pick up a new switch after work today?

 

[Jim L.]

I think that I would check the grounds first.

Imagine a battery, switch, and relay coil in a circuit. The switch is ON and the coil builds its field. When the switch is pressed OFF, the field collapses. When the field collapses, the voltage across the relay coil will go higher than the battery voltage.

Don't know if that is your situation. But it is the only way I can think of if the voltage is really going briefly above battery. And you can treat a flaky ground as a switch.

 

[sula bob]

Nearly two months later and all was fine until it wouldn't start after running all day Friday. Changed the ignition switch and still no power. Checked all the grounds and they were fine. Checked the negative and positive wires on the battery and there was the issue. The red wire that has the black connector that slides onto a connector on the batter was the problem. The connector on the battery was rusty. Little bit of sand paper and some grease and everything is good to go!