Steered tag axle shift valve not connected
• Check power supply and ignition signal to the chassi expansion unit * Check wiring to steering valve * Check connectors to steering valve * Measure the voltage on the chassi expansion unit between pin B7 (signal) and pin B10 (ground) when steering valve is open. • Check CAN connection to expansion unit • Check wiring and connectors for the expansion CAN-bus • Measure the resistance (with the battery disconnected) between pins CAN_H and CAN_L. It should be approximately 60 ohm (one 120 ohm termination resistor in each end of the CAN-bus).
What you'll see
No driver-visible symptom recorded.
System reaction
• Functions dependent on the steering valve are degraded.
Diagnostic depth
If the steered tag axle valve is open but the current consumption below 200 mA on the chassi expansion unit between pin B7 (signal) and the steering valve connected to this pin is below 200mA
*Defect wiring - open circuit on the chassi expansion unit between pin B7 (signal) and pin B10 (ground) - short circuit to supply voltage * Defect connectors * Defect steering valve