Steering system is independent from drive. There is pressure switch screwed in to orbitrol(hydraulic unit under steering column) with two wires. When you turn steering wheel, pressure inside goes up resulting switch the sensor on, and start of hydraulic pump. You can bridge cables and check that steering starts work. If that, change sensor or try to adjust pressure pick-up point by slightli screw out small screw on the end of pressure sensor(between connectors). Let us know about effects, as it can help someone in future with similiar problem. Best Regards.

Check return voltage from pedal potentiometer under floor.
Should be arround 4.9 - 5.0 Volt in neutral position, and 8.0 - 9.0 if fully pressed. There are 3 wirings: positive 10V(supply), negative, and return voltage which has to be whitin correct range. You can adjust it by unscrew the pot and twist slightli until reach correct settings. Be aware, as if the truck is in the gear and you twist it too much, it will drive away!!! One more things: Sometimes potentiometer is faulty and loosing parameters on end range. Best to connect multimeter and check return voltage whitin full range by pressing slowly drive pedal to the floor and observe indications.

the power steering sometimes works when the fault happens but not all the time. the fault happens even on a fully charged battery

hello friend
when the machine is working well, you see the input voltages and output, and configures when she feels bad, see if there is anything on the accelerator, the steering circuit...
Ouvir
Ler foneticamente