I've got a Case 420 Skid Steer. Was driving it recently and it was running well. Stopped and it refused to start again. Turn the key and dont hear anything click on the relay. Pulled the key out and all the lights are still on!! They dont go off until I pull the battery. So, I turned the key to the "on" position and tried jumping the relay. It sparks but never turns the engine over. Please note that I can spin the driveshaft with a large pry bar, so I know its not locked up. Checked voltage and am getting 12.3 volts when testing. Verified all fuses are good and swapped some relays. All looks good. Im at a loss. Any help is appreciated.
Does this machine have a foot pedal to operate the 4in1 aux hydraulics? If so, there is a switch mounted to the control valve which acts as a safety to shut the machine down if you bump the pedal when exiting the cabin with the engine going. Possibly, this has open circuited. I have replaced a few of them in the past - well worth a look. Trouble is you need to raise the loader frame to tilt the cabin, to gain access to the valve. I hope you have another machine available.......
Yes, the machine has a foot pedal. I have moved it in all directions and it does not change the outcome. I have doubled checked all wires and dont see anything that stands out. I think the most alarming thing for me is that I have to disconnect the battery for the instrument panel to stop beeping / flashing. I take the key out and it's still on. Put the key back in and try to start it and the lights don't change or do anything different. Very bizare.
Is the key switch loose? I've seen a key switch twist and short wires before. I've also see some key switches rattle apart internally. On the suggestion about the open switch on the peddle. The only way to make sure it is working is to test the switch with a volt or ohm meter. If you have a way to get at the wiring to the switch you can use a probe on it.
I removed the instrument panel last night and made sure that it was fastened to the plug. I also removed the 4 wires to the key switch too. I got the same results whether or not the key switch was plugged into the 4 way connector. It didn't change anything. still had to disconnect the battery to make the lights go off.
The control panels on the 400 series are a known replacement issue. I had to replace one in a 465. I don't recall having the same symptoms you are having, but the control panel can be an issue. I would check the power lines from the battery to starter and see if something went to ground. Especially in those smaller machines, a lot of stuff crammed into a small area.