I have a CASE 590SN. Has code 4047 (charge pressure switch is closed with no frequency input to the trax controller) and code 4205 (system cannot engage required gear) amongst other codes. Only code that is active until you drive it is 4047. Then it is stuck in first gear. looking for someone who has seen this issue before or has any input. I tested the charge pressure sensor and the harness from there up to the trax controller. Unit is stuck in 2nd gear I believe but it may be 1st. Last diag step I have access to are temporarily replace trax control module and retest. We are no longer a CASE dealer and only have the software to hook up and read codes. Any help is appreciated just trying to help a long time customer. Codes stored in ECU are 4047,4205,4206,4496,4830,4206.
You probably have already but I'd check all harness connections fuses, relays along with sockets they fit in.
Yes I have I’m stumped on this one. Only code that will stay active now is 4047 and the transmission will only go into 1st and second gear. If you put it in 3rd it stays in second and if you put it into 4th is switches to 1st gear.
Have you checked ohms on speed sensors?
Transmission has new speed sensor and the engine RPM is reading ok. Should I be testing anything else?
The computer is readying engine speed, transmission input and output speed, and vehicle speed in the data monitor
Well hmmm that last post was just a thought. I worked on a lot of Case machines but not many power shift backhoes. Do you have a service manual to chase the cause of your fault code?
I have had the shift rail switches do all kinds of funny things but you should be able to read whether they are open or closed in EST. You may want to pull the plugs behind the shift rails and verify they are traveling all they way into position.
What reference would they be under in EST? I do not have access to the service manuals as we are no longer a case dealer and can’t get into ETIM. Where are the shift rails located on the transmission?
Only code I have active is 4047. I have yet to be able to make anything else come up. Trans is indeed stuck in 1st or second. When I put it in 3rd it shows I have 2nd selected and when I put it in 4th is shows I have 1st selected. I’m assuming it’s in a limp mode.
Sorry I have not been on for a while but you can look at the gear commanded switches and activate each one buy removing them from the trans and manually operating them to see if the signal goes from off to on. I will have to verify the measurements but you can also remove the plugs from the trans case and measure the shift rail travel