MF 6490 fault/error codes

[gone]

My Tier3 MF 6490 is throwing up T2.54 and T2.56 error codes, any ideas?
Is there anywhere I could get a list of the codes?
TIA

 

[Lofty1984]

Boost sensor faults or its unplugged

 

[Southmec32]

The boost sensor has failed and is located behind rh front cab mount. Not easy to get to.

 

[Southmec32]

254 is sensor dis connected and 256 is plausibility error. 255 is calibration values.

 

[jthomsonagri]

Is it a dealer only job to calibrate? got a 6490 giving code t2.55.

 

[MasseyMatt]

t2.55 is power boost that needs calibrating. you can do it yourself no problem from what i remember when it happened our 6480 set the engine to 1500 rpm and hold both the diff lock and 4wd buttons at the same time for about 10 seconds. Cp will come up on the screen and that will be the end of your problem. We found that if the tractor was spinning it would bring up that code

 

[Southmec32]

Just diff lock switch needed not 4wd

 

[jthomsonagri]

t2.55 is power boost that needs calibrating. you can do it yourself no problem from what i remember when it happened our 6480 set the engine to 1500 rpm and hold both the diff lock and 4wd buttons at the same time for about 10 seconds. Cp will come up on the screen and that will be the end of your problem. We found that if the tractor was spinning it would bring up that code

Just diff lock switch needed not 4wd

Tried this today using just the diff switch and diff and 4wd together. All that happens is I get cp come up and then a few seconds later the error code again. Should I be doing anything once cp comes up?

 

[Southmec32]

No just release switch try without 4wd switch . I have never used it and never had a prob

 

[jthomsonagri]

No just release switch try without 4wd switch . I have never used it and never had a prob

Tried it like that and still no joy. Just to confirm, revs set to 1500? I tried with hand throttle and preset button but both gave the same outcome.

 

[Southmec32]

Yeah if cp is coming up it is working but not holding calibration somehow .has it ever come up with error t254 or t256

 

[jthomsonagri]

No been lucky with it I think, no error codes in 4 years up until this spring. I would guess if the sensor was faulty or the wiring dodgy I would have more codes. Would the fact that I hadn't activated the gearbox before doing the calibration perhaps have something to do with it? The tractor was warm when I did it but all I did was start it and then try the calibration, maybe I should have moved it first.

 

[Southmec32]

Try this

 

[jthomsonagri]

Thanks for that. One thing that stands out from that is that the three position PTO switch was in the middle position rather than off. I shall give it another go as per instructions and see what happens.

 

[jthomsonagri]

Tried it again as per instructions and it worked for all of about 2 minutes. Now got 254 and 256 coming up so the sensor must be at fault. Going to check the wiring, does the tractor have to be split to change the sensor?

 

[Southmec32]

No you just remove rh front cab mount support. It is a bit tricking getting into place

 

[Yorkshire dano]

make sure air con, fan,l lights etc are off

 

[gone]

Fault 94
Coming up now any ideas?

 

[Always wandering]

Fuel filter pressure
I ructions in fuel lines
Dirty filters
Failing fuel lift pump

 

[gone]

Fuel filter pressure
I ructions in fuel lines
Dirty filters
Failing fuel lift pump

Thanks,
I think I am after getting a a fill of poor diesel when ploughing for a neighbour.