Fault Code 74 on display

Caterpillar EC25EN model 5,000 capacity forklift has a fault code 74 on the display. We took it off charge and now has this code and none of the hydraulic controls work. No lift, tilt or auxiliary functions. We unplugged the battery and put it back but the code 74 stays on. Looking for some information on what can cause this problem. The truck is just out of warranty and what a little help before we call out a mechanic.

Code 74 is an error in the lift valve lockout solenoid. The solenoid sits on the lockout valve. A problem with the solenoid or the actual valve will cause this code and all hydraulic functions will be inhibited.

The test for a bad solenoid is pretty straight forward. The resistance shoul be about 9 ohms. This is different that most other solenoids that should ohm out at about 45 ohms. Just diconnect the solenoid connector and use your meter to test it. All you have to do is remove the floor baord to access the connector for testing.

If the solenoid is good, the valve may just be stuck. You can actually give it a tap with a small hammer, cycle the key off then on and see if the fault code 74 goes away. If so, replace the lift lockout assembly.

On your Caterpillar model EC25N the solenoid and valve assembly sits right on top of the main valve bock assembly under the controls. To replace the valve, just release the controls so they move forward. remove the 4 torx screws that hold on the cover, remove the small phillips screw in the top and slide the solenoid off. Use a wrench to remove the valve from the block. See picture below.

I have replaced the valve and solenoid, I still have error74 and 49?

If you are having both of those codes, I would first tackle the error 49 which is the steering code, possibly can relate to code 74 which is a different circuit