Network Sleep Mode

It reduces battery drain. It takes some minutes. Faults keep networks awake. Workshops wait for the network to sleep, which can take a while after locking, before measuring parasitic drain. Aftermarket devices that keep sending messages can prevent sleep. A scan tool or ammeter showing current that never drops points to a module that stays awake. Removing fuses one at a time can disturb the network, so many technicians measure across fuses instead.

Control units stop sending messages.

Modules that stay awake drain batteries. Wait before measuring drain.