The cab fan (M3) supply voltage is out of range (below 16V or above 32V).
1. Check if any other control system has a DTC for supply voltage out of range. If other control systems also has this DTC, check the voltage delivered by the 24V battery supply. 2. Check the supply cable harness to the cab fan. 3. Replace the cab fan.
What you'll see
No driver-visible symptom recorded.
System reaction
If the supply voltage is above 32V, the cab fan will shut off. If the supply voltage is below 16V, the cab fan will shut off or it will not run at full speed.
Diagnostic depth
The digital feedback signal from the cab fan to the climate control system (E17) is indicating that the supply voltage is out of range. The test is performed when the cab fan is running and the starter motor (M1) is not running.
Failures in the components or the cable harness that deliver the battery supply voltage to the cab fan.