Bobcat S250 controller

[808bob]

Im thinking I may have a bad controller. s250 530915219. Key on all the right panel lights come on, no start. Wait for a minute or so, then it will start. Right panel stays fully lit, no hour meter reading, so no codes. After the first start it will act different. Wait a few minutes and its back to the first start problem. Second start, Key on no right panel lights, wait a minute and the left panel gauges move, then it will start. All other functions seem to work ok. Battery is good,grounds are good. Ignition voltage at the key switch is 12+, key on its 8, engine running its 9.5.

 

[OldMachinist]

I think that you should still have 12+ volts at the key switch with it running. With it running check what the system voltage is at the large terminal on the starter is to ground. Should be between 13.5 to 14.7. If the voltage is good there try swapping the switch power relay for one of the other relays. If all that fails I'd re-check the grounds to the controller and panels.

 

[Tazza]

I think that you should still have 12+ volts at the key switch with it running. With it running check what the system voltage is at the large terminal on the starter is to ground. Should be between 13.5 to 14.7. If the voltage is good there try swapping the switch power relay for one of the other relays. If all that fails I'd re-check the grounds to the controller and panels.

I'm with OM on this too, with the machine running, your +12v wiring should be 13-14v as the alternator will be charging, pushing the voltage up. 8v seems very low to me.
I wonder if you could cheat and run a tempory wire from the +ve terminal to the 12v line at the box that is currently low. It could be a bad fuse connection in the fuse box causing high resistance/lower voltage.

 

[808bob]

I'm with OM on this too, with the machine running, your +12v wiring should be 13-14v as the alternator will be charging, pushing the voltage up. 8v seems very low to me.
I wonder if you could cheat and run a tempory wire from the +ve terminal to the 12v line at the box that is currently low. It could be a bad fuse connection in the fuse box causing high resistance/lower voltage.

The relays dont supply power to the keyswitch. 12 volts jumpered in doesent work either. Where are all the grounds located?

 

[Tazza]

The relays dont supply power to the keyswitch. 12 volts jumpered in doesent work either. Where are all the grounds located?

There are multiple grounds, a main one at the battery to the frame and engine, then there are smaller ones all the way along the wiring harness, sadly you will need to trace along the harness to find them.