# 7740 shift issues



## Cantrellc123 (Jun 15, 2015)

My 7740 has the code E40 or E41 come up when I shift to 2,4,6,or 8th gear. It stops pulling immediately. I can turn it off and restart it and use 1,3,5,or 7th with no issues so long as I clutch it and shift to any of these gears bypassing any even numbered gear.
I'm guessing an electrical issue. 

Any ideas?


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## Fedup (Feb 25, 2014)

Error codes E40 and E41 don't appear in the listing for early model 16 x 16 transmissions, only the Quad Mod, which means your tractor is probably a 94 or 95 model? 
These codes indicate a short or open circuit to C3 solenoid. This fits your narrative as C3 clutch is engaged in all even numbered speeds. It could mean a wiring issue in the harness leading to the C3 solenoid, or a bad coil on that valve. The wiring could be difficult to trace, but might be necessary if the coil itself is NOT the problem. 
I would start with the coil. There should be four coils, all in row on the power shift valve located on the right side of the transmission housing. All should be identical part numbers so they can be interchanged with no ill effect. The third coil back from the front should be for C3. My diagrams show it has a pink and a blue wire leading to it. Remove it and one of the others, then trade places. Put the wires back in the original order and give it a try. If the coil is bad, the problem(and error code) will change. If you still get the same result, then more trouble shooting is required.


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## Cantrellc123 (Jun 15, 2015)

I switched the third and fourth solenoid wires. They were long enough to unplug and switch from C3 and C4. The problem remained the same. I see E41 way more than E40. 
So I assume this leaves a wiring issue? Any advice?

I'm not certain what year model it is. It has both Ford / New Holland on the Sheetmetal if that means anything.


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## Fedup (Feb 25, 2014)

Switching wires between coils for any two solenoids should cause multiple issues and solve none. Switch the coils and put the wires back where they belong. Then see what happens.


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## Cantrellc123 (Jun 15, 2015)

I switched positions of C2 & C3 solenoids and plugged all up correctly, the problem remains the same with no change noticed.

Thanks for the help so far by the way. 

Cantrell


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## Fedup (Feb 25, 2014)

Considering what you've given us so far, my thoughts go to either a bad circuit in the wire harness between the computer and the solenoid valve or possibly the computer itself. They have been known to fail in many ways. There are at least two harness connectors that might be involved. A large one up under the dash and steering column area, and another smaller one under the cab, for the transmission extension harness. You might try separating and re connecting them for effect. the computer is in the cab, on the right side near the side window, under a panel secured with four philips head screws. There is a harness connector on on end of it, which when removed will allow you to check continuity through the harness between the computer and various points on the tractor(like the C3 clutch coil). Should you wish to go that route, I'm sure I have a book somewhere with the pin numbers and color codes for the circuits involved.


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## Cantrellc123 (Jun 15, 2015)

Any info you can provide will be helpful I'm sure. I'm going to call in reinforcements and the more I know the quicker we can resolve this issue. 

Thanks again.


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## michał1234 (May 31, 2018)

I have same error codes - E40 and E41 in my my New Holland ts 90 but they are appearing anly when transmission is swiched in turtle any adwises where to start looking for problem


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## Perry Harvey (Feb 9, 2020)

Cantrellc123 said:


> My 7740 has the code E40 or E41 come up when I shift to 2,4,6,or 8th gear. It stops pulling immediately. I can turn it off and restart it and use 1,3,5,or 7th with no issues so long as I clutch it and shift to any of these gears bypassing any even numbered gear.
> I'm guessing an electrical issue.
> 
> Any ideas?


Did you ever sort out the problem u with losing even gears


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## Cian123 (Jun 19, 2020)

Perry Harvey said:


> Did you ever sort out the problem u with losing even gears


Any resolutions on this issue, am having the exact same issue with a NH 8340.....


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