Tronic KH 972 Operating Instructions Manual page 18

Note:
It is possible that the cigar-lighter only functions
with a switched-on vehicle ignition. If you are
unsure, consult the vehicle handbook.
Caution!
For vehicles in which the cigar lighter resp.
onboard power sockets also function with a
switched-off vehicle ignition:
Only use the quick battery charger with the
engine running. Otherwise, the vehicle batteriy
could be completely discharged by the use of the
quick battery charger!
- 16 -