Cigarette Lighter Battery Charging Function
A trickle charger can also be connected to the cigarette lighter. However, the cigarette lighter is supplied by the body-zone consumer isolation circuit (VA-K) via a relay.
If the "terminal R Off" signal is present for more than 60 minutes, that relay will be switched off by the consumer shutdown function. That would mean that a charger connected to the cigarette lighter would be disconnected from the battery.
To prevent this, the consumer shut-down function can be deactivated. This is performed by the following procedure:
Slide the battery switch off and on again twice within two seconds.
The function is cancelled by: "terminal 15 On", switching the battery switch from "OFF" to "ON" or failure of the battery voltage to reach 12.6 V after 6 hours of charging.