sent you something to help you troubleshoot that problem :o)

Thanks for the reply.
The joystick is finger joystick. when i operate the pump sound is different depending on how I act. No eroor codes.
I have 3 solenoids down under bracket. When operating the joystick not see any voltage on solenoid. Believe these are proportional solenoids. I suspect computer who control the mast. If you have some documentation on this model truck send to me to study.
Regards

Hydraulic system

Problem:
operates abnormally or does not operate at all.

Possible Cause: Remedy:
1. Malfunction of pump Check pressure, or replace pump.

2. Clogs in relief valve Disassemble and clean relief valve.

3. Malfunction of relief valve Check according to service procedures.

4. Worn cylinders Repair or replace.

5. Excess load Check circuit pressure.

6. Cracking in valve Replace valve.

7. Low oil level in tank Add oil.

8. Clogged filter in circuit Clean or replace filter.

9. Flow restriction in circuit pipe Check pipes.


Now my question to you is when you activate the hydraulic motor how fast does it ramp up to? Can you distinguish any differentiation in the sound of the motor when you move the lever? (does it change AS YOU MOVE it? Or does it stay the same speed after it first ramps up?

And as was already suggested you will need to take pressure readings at the pressure port to see what pressure you are getting. Are there any error codes popping up on the display at any time when you operate the hydraulic system or truck functions?

I hope I can help. The kt trucks have two control valve options, finger tip joystick or mechanical lever and the control valves are different. The pump motor control has two options, chopper control or contactor type. I would guess your pump motor control is working. The chopper type varies the motor speed. I would check the pump pressure at the control valve pump pressure inlet. I think there may be a 1/8 pipe plug tap. You should see about 2625 psi relief with the tilt dead headed. The relief is on top of the control valve to the left. Let me know if you need more information. Just post you control type and re-check your serial#. I could not get it to come up.