Plausibility test in self test indicates hydraulic failure
• Low oil level in system, check for DTC 0x0246 (Low hydraulic oil level in Motor PumpUnit, MPU). • Check for hydraulic leackage on - Hoses - CVU - MPU • Look at the speed feedback signal from MPU make sure it also runs by listening during self test. • Perform an air evacuation procedure. If the fault only occurs at very low temperatures(-30C), the oil might have to be replaced. See service litterature for recommended oil quality in cold climate. DTC becomes passive if Diagnostic SelfTest (requires Parking Brake to be applied) completes without any plausible error detected.
What you'll see
No driver-visible symptom recorded.
System reaction
Red Steer tag axle fault warn EST in released or fixed mode
Diagnostic depth
Operating piston in large diagnostic selftest indicating hydraulic failure.
• CVU hydraulic leakage - Counter balance valve broken • MPU unit leakage • MPU not operating on request • Air in the hydraulic system • Hydraulic leakage - Hydraulic hose broken - Hydraulic connectors loose - Cylinder piston rod seal is degraded - MPU oil reservoir seal has failed • Extremely low temperature has caused the hydraulic oil to solidify