Problem solved!!! First of a big thanks to Little Forker for all the tips and support! Lastly another big thanks to swoop223 for the great tip.. Problem was just a bad connection on the main fuse block. Did a wiggle test and immediately truck response to command as in lifting.


Thanks guys, I really do appreciate your help!!

Pump pressure is constant up to the control valve. When a function is called for the dump valve closes and diverts the fluid to the valve spools instead of dumping back to tank. The sensors on the control valve signal the ecu to turn off the dump valve and enable the flow through valve normally and as you pull the lever it sends fluid to whichever function you are calling for. At the same time it signals the throttle control to rev up the engine.
If there are any faults detected it disables everything and should signal the ecu to display a fault code associated to the type of fault and component detected. Display a mil light or display a code with associated symbol.
If there are no codes displayed at all then it may not be seeing any input signal. So yes it might be a high possibility the sensor on the levers are not picking up lever movement.
One other thing is i would check and make sure there are no fuses blown and check connectors in that circuit.

I agree that the sensor is useless if there's no pressure there for it to detect. I do appologise, I had misread some of what you had put in your first message.

All the spools are moving fully and freely on the valve pack?
There's not too much more I can think of without pressure testing the system. The only other thing I can possibly think of is that the system has sucked in air at some point, try removing the outlet hose from the tank and fill it up with as much oil as possible? It's a long shot but iv had it happen to me before on other linde models and is the only other thing I can think of without pressure guages.

The sensor might be defective, my question now is how does this relate to the pressure being built from tandem pump. for what i understand, with or without the sensor it should lift without rpm, but slowly. Don't you think so, cuz what i notice is that it doesn't lift at all. What I notice also is that I can rev the engine with the directional pedals, forward or reverse it revs up to 2300 rpm, and while revving I pull down the lift lever for the mast to go up but all it does is rev but no movement.

Plus if there is no pressure, the pressure sensor would be useless for it doesn't sense any output pressure.

My apologies if I'm very ignorant but I also see that if there is no pressure the sensor will not work also. I will replace the sensor just to be out of curiosity. any more suggestion?? Thanks

There is a sensor on the valve pack, this controls the engine revs when the hydraulics are activated. The part number will be printed on it (there are two types) I suspect this sensor needs replacing or may have debris in the port hole.

Hi Little Forker,

Many, many thanks for your prompt reply. The serial number is

H2X350M0272720

It doesn't rev up when ever I pulled all the levers, UP lever, TILT lever, and SIDE SHIFTING lever.

What's the serial number for the truck?

Do the engine revs increase when you activate the hydraulics?