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Drivers Door Lock

Drivers Door Lock
The drivers door lock on the (E85) Z4 is an Low lock. The same lock was previously fitted as a Low lock on the E66. Compared with the lock used on the E46, this unit incorporates two Hall-effect sensors. The general module analysis the signals from those sensors and locks/thief proofs or unlocks the vehicle accordingly.
The order of the signals determines how they are interpreted, i.e. as lock/thief proof or unlock. By the use of two Hall-effect sensors and the intelligent analysis of their signals, errors when locking/thief proofing or unlocking the vehicle are prevented.
Detection of a rising edge starts a counter which is stopped again as soon as both signals (SNU 1 and SNU 2) are present. Within a valid time window, the request to lock/thief proof or unlock is set. As long as the key is held in the turned position, the request to lock/thief proof or unlock remains valid. If either of the two signals (SNU 1 or SNU 2) is lost, the request is reset again.