L3901 HST dies suddenly

[ken erickson]

Other than the OP's original posting stating 3 codes are showing, P0606, PO627 and P0629 there has been no discussion as far as these codes. Might these codes not point to a possible solution if they are properly diagnosed?

 

[TheOldHokie]

Other than the OP's original posting stating 3 codes are showing, P0606, PO627 and P0629 there has been no discussion as far as these codes. Might these codes not point to a possible solution if they are properly diagnosed?

That would be a good start. Unfortunately P0606 indicates an ECU problem so the SCV codes may not be definitive. I suspect Kubota techs have seen this combination more than once and may know the cause or where to go next. Short of throwing parts at it a scan tool is probably needed for additional diagnosis.

Dan

 

[ken erickson]

Dan,
Thank you for your reply! Not sure if the "angry" emoji was meant for me and asking about the code situation? If so it seems like a valid question to ask.

That being said, I would put my emphasis on getting the ECU and P0606 code situation sorted along with checking for any physical damage to wiring or electrical components.

 

[TheOldHokie]

Dan,
Thank you for your reply! Not sure if the "angry" emoji was meant for me and asking about the code situation? If so it seems like a valid question to ask.

That being said, I would put my emphasis on getting the ECU and P0606 code situation sorted along with checking for any physical damage to wiring or electrical components.

The angry emoji was a fat finger accident and I removed it.

As best I can determine, for a P0606 fault code:

A 1077 SPN indicates a fuel pump related problem.

A 553527 SPN indicates a problem with the CPU in the ECU itself.

Dan

 

[Hugo Habicht]

That would be a good start. Unfortunately P0606 indicates an ECU problem so the SCV codes may not be definitive. I suspect Kubota techs have seen this combination more than once and may know the cause or where to go next. Short of throwing parts at it a scan tool is probably needed for additional diagnosis.

Dan
View attachment 163179

Three faults appearing the same time?

I would focus on supply voltage, fuses, ground connections etc. A CPU or memory fault in the ECU is highly unlikely.

My friends tractor showed all kind of error codes and CAN bus faults when a fuse was blown due to a wire short. If we would have followed the work shop manual we would still be searching for the problem.

And yes, 100%, a good experienced Kubota technician will know what the fault is.

 

[TheOldHokie]

Three faults appearing the same time?

I would focus on supply voltage, fuses, ground connections etc. A CPU or memory fault in the ECU is highly unlikely.

My friends tractor showed all find of error codes and CAN bus faults when a fuse was blown due to a wire short. If we would have followed the work shop manual we would still be searching for the problem.

And yes, 100%, a good experienced Kubota technician will know what the fault is.

Faults spawn faults. My wife's 325Xi recently started lighting up the instrument panel with Xdrive, steering, stabilty control, and brake system warning lights.

Plugged my scan tool in and it was logging an endless stream of different errors from a boatload of different sensors and ECUs. But the largest percentge by far was left and right front wheel speed sensor faults. Took it to my local shop were they put it on a lift and a visual inspection quickly found that corrosion had eaten up the speed sensor tone rings on both front axles. Two new axles and all was well again...

Dan

 

[Mark_BX25D]

Again I am not an expert

Well, you may not be an expert, but you clearly think you know more than I do about this system, and you clearly DO, so I'm just going to shut up and learn!

 

[whitetiger]

DO NOT REMOVE THE INJECTORS FROM A COMMON RAIL FUEL SYSTEM!!!!!!!!
It does not have an injection pump, and the injectors will only inject when the ECU tells them to.
If you do not fully understand the Common Rail injection system, do not mess with the injection components.

Messing around with this fuel injection system will result in a lot of whining about the $8,000 —$18,000 repair bill.

TSB-2023-035-E-R3
Issue: The engine may fail to start, and DTC code P0605 or P0606 may appear.
Solution: If DTC P0605 is present, replace the engine ECU with the updated engine ECU in the chart below for your unit per the Workshop Manual and complete a manual DPF regeneration per the Diagnosis Manual.

If only DTC P0606 is present, update the ECU Software to the latest software per the chart below for your unit and clear the DTC codes (The DPK file can be downloaded from the Machine Software page on K Service).

Warranty will cover for 8 years from purchase.