262D Cat 44-1

I have a cat 262D Crank No start only getting fault code 44-1 I have unplugged all sensors in the circuit to check for short to ground everything is good, when 44-1 is active I only have 4.2 volts on my sensors when there should be 8V Okay if I unplug battery and let ecm reset code goes inactive I then turn key on and sensors have its correct voltage of 8v when I got to crank it I lose voltage down to 4.2 I only loose the voltage when I go to crank it and it doesn’t get its 8v back until I unplug battery

I think you mean 41-4? Please crarify, or post picture of code as it appers. Also a machine serial number helps us understand exactly what machine you are working on.

Yes I had a mis typo and I can’t edit it it’s 41-4 machine serial DTB04543

That makes sense. 0041-04 is sensor supply voltage below normal. Given that yours goes down to 4.2v instead of zero, it's most likley a faulty sensor is pulling it down. This is a diagram of your 8V sensors. Try unplugging them in turn, cycle power and see if the code goes away.

Cmark said: That makes sense. 0041-04 is sensor supply voltage below normal. Given that yours goes down to 4.2v instead of zero, it's most likley a faulty sensor is pulling it down. This is a diagram of your 8V sensors. Try unplugging them in turn, cycle power and see if the code goes away. View attachment 365318 Click to expand... That’s exactly what I done except I didn’t power key each time , ET Refreshes itself during incoming and outgoing faults

Cmark said: That makes sense. 0041-04 is sensor supply voltage below normal. Given that yours goes down to 4.2v instead of zero, it's most likley a faulty sensor is pulling it down. This is a diagram of your 8V sensors. Try unplugging them in turn, cycle power and see if the code goes away. View attachment 365318 Click to expand... And my machine doesn’t have lift cycle pressure sensor Or Self level limit sensor it has a switch tho and it doesn’t have inclinometer

so the next logical step is to unpin pin 56 at the Machine ECM and see if the fault goes away

Cmark said: so the next logical step is to unpin pin 56 at the Machine ECM and see if the fault goes away Click to expand... If that’s the case I wouldn’t receive 8v power to sensors mainly engine speed (CPS) so it still wouldn’t allow it to start right?

Correct. It still may not start but that's not the goal at the moment. The goal is making the CID0041 go away. The fault code should either go away or change from FMI04 to FMI03. If that's true then it's unlikely your ECM is the problem. It points to a partial short to ground on the +8V supply.

Cmark said: Correct. It still may not start but that's not the goal at the moment. The goal is making the CID0041 go away. The fault code should either go away or change from FMI04 to FMI03. If that's true then it's unlikely your ECM is the problem. It points to a partial short to ground on the +8V supply. Click to expand... Follow Cmarks direction and you'll be good. Simon C