Low hydraulic oil level in Motor Pump Unit (MPU)
• Check the oil level in the tank: - If level is low. Fill up the system with recommended hydraulic fluid. - Check the system for leakages • Check wiring and connectors: - Disconnect the T1000 sensor connector, and the E1003 ECU connector A (the green connector). - Measure the resistance over the cable, through connector pins E1003::A9 and T1000::2 - Measure the resistance over the cable, through connector pins E1003::A7 and T1000::1 - The resistance should be 0 ohm. • Check the sensor T1000: - Disconnect the sensor cable and measure the resistance over the sensor pins. At normal fluid level the resistance should be 0 ohm, and at low level the resistance should be infinite (OL).
What you'll see
If there is a leakage in the system plausability tests will detect this as soon as the oil level goes below the inlet level of the hydraulic pump. In that case a red warning is shown to the driver and aditional fault codes will be set, indicating mechanical fault or non correct system behaviour.
System reaction
Yellow Steer tag axle fault wa ESTA in fixed centred mode
Diagnostic depth
The hydraulic oil level sensor (T1000) in the Motor Pump Unit reports low level.
• Low oil level in the tank • Defect connectors • Defect wiring - open circuit on sensor signal or ground • Defect sensor (T183) • Truck placed in an extream slope(tipping ramp).