Case 420CT Series 3 won't start intermittently, even right after turned off.

[HandyDan]

Hey guys, I am new to the forums. Looking forward to being a member.

I recently purchased a 2010 Case 420ct series 3 with 1200 hours and have been running into issues. Problem is, I will be operating the machine, turn it off and it won't start back up again. Hydrostatic and oil pressure warnings are flashing and beeping, it also flashes 11 volts on hour readout.

At the start I figured it was a sensor and had to do with the angle of the machine. I would tow it level and it would start again, but I think that could have just been coincidence. I replaced the hydraulic filter and hydraulic pressure sensor to no avail.

I found that the 25 amp starter fuse was blowing, so I moved on to the starter relay as it wouldn't even crank a little with the key on ignition, but found that bridging the relay while the key is on does nothing. Right now I am stuck on the possibility of starter or battery, but the two flashing hydrostatic pressure and oil lights have me stumped.

Key points:
Problem occurs right after shut off and intermittently corrects itself.
Hydrostatic light flashing Oil Light flashing
11 Volt flashing on readout
No crank at all
Replaced hydraulic oil filter (no help)
New hydrostatic sensor (no help)
Starter fuse blowing occasionally
Bridging starter relay does nothing (no crank at all)

Any insight is appreciated

 

[HandyDan]

Update: Battery ok.
Going to check wiring as the starter relay fuse blows a lot!
Still no idea why those lights are the ones flashing

 

[DIYDAVE]

Check ALL grounds, starting at the battery...

 

[Canuck Digger]

I ain't no mechanic, but does sound like a ground or contact issue of some sort...

 

[HandyDan]

It is sure looking that way. I guess the ECU just doesn't like it and that's why I'm getting the lights.

 

[GaryHoff]

So if you jump the starter relay, (pins 87 to 30) the machine will not crank? (also you should have 12v at pin 30)
When does the starter relay fuse blow? If the starter relay fuse is blowing then you likely have a shorted wire from the starter solenoid or a failed starter solenoid.
Does this machine have auxiliary hydraulics? Does it have the foot pedal for the auxiliary hydraulics?

 

[jamesoro]

I have run into a similar problem with our case 420ct. After it has been used for awhile and shut down it fails to start, identical to HandyDans except no blown fuses. If you let it cool down it will start. While it's hot I can hear the clicking but no go. It may or may not catch while it's hot. I notice there is a fuse looking thingy coming off the selenoid that has no fuse in it. Does anyone out there know what it is? I cleaned up the ground connecting to the frame that comes off the starter and cleaned up the connector junction that sends power up to the grid heater but don't see anything obvious. HandyDan, did you figure out your issues yet? I also took in the starter and they put a new selenoid on the starter. Could I have been sold a bad selenoid? Thanks James

 

[soilmover2]

I have found that the battery disconnect switches get corroded inside. also, the terminals on the outside of it will break but still look attached until pulling on them. check all grounds