The U30 12V supply to the climate control system (E138) is below 8V.
1. Check if any other control system has a DTC for low voltage. If other control systems also has this DTC, check the voltage delivered by the 12V battery supply. 2. Check the battery supply cable harness to the climate control system.
What you'll see
All actuators connected to the climate control system will shut off. LED indicators will be deactivated.
System reaction
All actuators connected to the climate control system will shut off. LED indicators will be deactivated.
Diagnostic depth
The supply voltage is measured by the climate control system. The test is performed continuously if the starter motor (M1) is not running.
Failures in the components or the cable harness that deliver the battery supply voltage to the climate control system.