Introduction

Introduction
This chapter describes the alterations to the central body electrical system (ZKE), electrical consumer unit shutdown (VA) and sleep mode as compared to the E46 electrical system.

Changes compared to E46
Consumer unit shut-down
There are 2 outputs for consumer unit shutdown.

Sleep mode
New conditions

Kbus messages
New messages

System Functions
Consumer Shut down
The outputs VA1 and VA2 are available for consumer unit shutdown. The general module 5 has been expanded. There is now a second output available for consumer unit shutdown (VA). The consumer unit shutdown function switches consumer units to Sleep mode after 1 6 min.

Consumer unit shutdown 1 (VAT)
Consumer unit shutdown output 1 is factory configured as a pulse width modulated output. The consumer units connected to consumer unit shutdown output 1 are the following:
^ Storage compartment light
^ Trunk light
^ Reading lights
In the event of an overload or short circuit, consumer unit shutdown output 1 is switched off by the general module 5 unless there is no load connected to the output (open load).Once switched off, the output is switched on again by terminal R OFF/ ON provided the fault (overload or short circuit) is no longer present.

Consumer unit shutdown 2 (VA2)
Consumer unit shutdown output 2 is available as a permanent general module 5 output. Consumer unit shutdown output 2 is overload and short circuit proof. The consumer units connected to consumer unit shutdown output 2 are the following:
^ Illuminated shifting gate on centre console (USA version)
^ Sequential Manual Transmission control unit
The permanent consumer unit shutdown output 2 is intended for electronic control units. The electrical control units require a permanent output as otherwise they would not be able to function.

Sleep Mode
The preconditions for Sleep mode are the following:
^ Window regulators deactivated for 1 s
^ Consumer unit shutdown and interior lighting passive
^ Diagnostic mode not active
^ Kbus in Sleep mode
^ On Go to Sleep Mode signal after 1 s or within 30 s of the anti-theft alarm system being armed

K-Bus Messages
The K-Bus now contains messages that may be addressed to all or multiple control units.

Diagnosis
Consumer unit shut-down
The diagnostic capabilities of the general module 5 have been extended. The general module 5 can distinguish between the following load conditions at the consumer unit shutdown outputs:
^ Overload
^ Short circuit
^ No load connected (open load) The various faults can be diagnosed.
Consumer unit shutdown output 2 (VA2) is overload and short circuit proof. An overload is detected by the general module 5.

Door mirrors
Introduction
The functions of the door mirrors on the (E85) Z4 are largely the same as on the E46.
Options offered on the (E85) Z4 are electro chromatic mirrors, the mirror folding function and the winter package.