MX5800 P0605 Code Help! **UPDATE**

[SkylineAcres16]

That's an interesting theory lugbolt

 

[tgarber22]

Dang I think I've just experienced the same thing. Dead battery. Replaced and P0605 error that won't stay cleared and I can't start the tractor. Tried to jump it as well so maybe that could be a culprit. Very information read. What other options do I have besides unplugging can connectors

 

[tgarber22]

Correction..I had starter sol. Cable disconnected. Now it just turns but no start

 

[SkylineAcres16]

Keep us updated on what you find out...hopefully it isn't the ECU like mine was

 

[whitetiger]

I still can’t believe they did this to off-road ag equipment

Actually, it started showing up on larger Ag equipment in approx the mid-1990s, about the same time as the US auto industry began to use it.

 

[tgarber22]

Keep us updated on what you find out...hopefully it isn't the ECU like mine was

We're you ever able to start the tractor with the P0605 code?

 

[SkylineAcres16]

No

We're you ever able to start the tractor with the P0605 code?

No, it never started again until a new ECU was connected. It wouldn't even communicate with the dealers laptops when plugged in. They tried 2 of them

 

[GreensvilleJay]

well the old ECU is YOURS ! be sure to get it back..... odds are replacing the CANbus interface chip ($1) could get it 'up and running'.Anyone with SMT R&R can do that.

sadly ,less than $10 worth of 'electronics' could have protected the ECU from being 'fried'.

Was taught to design 'controllers' as if they were satellites..you have ONE shot to design right,then they're in orbit, forever and no service guy ( BTW this was preShuttle days.....) I never 'lost' any of my remote energy panels,some 15 miles away on 'direct wires', even when nearby lightning bolts took out computer, terminals, etc. so I KNOW it can be prevented.

 

[tgarber22]

Just got it back from taking the tractor to the dealer. They put in "known good" ECU and still read the code. He did some quick checks on the pin-outs, more than discussed in the WSM, and said one of them was not getting power. I opted to leave it on the trailer and take it back home and work on tracing it down. He suggested replacing the wiring harness, but I'd like to find the issue on my own time first before I do that. He said the power wasn't coming through here, but I'm not sure what pins are supposed to get power and which aren't. Anyone know that answer? Haven't found it in the WSM yet

 

[North Idaho Wolfman]

Just got it back from taking the tractor to the dealer. They put in "known good" ECU and still read the code. He did some quick checks on the pin-outs, more than discussed in the WSM, and said one of them was not getting power. I opted to leave it on the trailer and take it back home and work on tracing it down. He suggested replacing the wiring harness, but I'd like to find the issue on my own time first before I do that. He said the power wasn't coming through here, but I'm not sure what pins are supposed to get power and which aren't. Anyone know that answer? Haven't found it in the WSM yet

Based on what you have highlighted in RED, the only "power" coming in on any of those pins is (-) Ground , not (+) positive, the rest of the pins are outputs.
So look at the ground connections.

 

[GreensvilleJay]

if P0605 really means 'flash rom cpu abnormality'.....
brings up LOTS of questions....
1) does this ECU control the display, that shows you the error code ?
2) if not HOW does the 'error code' get transmitted from ECU to the display ?

If #1 is true, then the 'known good' ECU would have 'cleared' the error code< well, actually it would not be IN the ECU,so can't be displayed.
Also if #1 is true , then power ( +12 and gnd ) are good as ECU IS functional..it's displaying information.

Since the 'known good ECU' gave the EXACT same code, it's NOT the $$$ ECU, but the error code 'suggests' it IS an 'internal' problem INSIDE the ECU, making it 'bad', but the 'known good ECU' says the same thing....so it must be 'bad' but it's a 'known good ECU'.......arrrrrgh.

Sadly ONLY the original programmer KNOWS why that P0605 came up.