E46 LSZ Control Unit: Notes
WARNING: This page does not describe the selected car, but rather 37 other vehicles, including the 2006 BMW 330Ci, 2006 BMW 325Ci, 2005 BMW M3, 2005 BMW 330xi, and 2005 BMW 330i. However, it is still accessible from the selected car via links, so may be relevant.
The LSZ control unit is the control unit for the light switch cluster.
Since the model year program in September 2001, the light switch cluster of the E46 has been overhauled as follows:
- Pulse-width modulated power supply for the vehicle lighting: The voltage for the vehicle lighting is output as a pulse-width modulated signal. The voltage has a fixed frequency of 80 Hz. This prevents lighting fluctuations when consumers with a high current draw are switched on.
- Separate outputs on the light switch cluster (LSZ) for the tail lights, brake lights, rear fog lights and bi-xenon lights
- Additional LSZ input for future dual-stage brake light (brake force display): There is an additional input in preparation for the dual-stage brake light (the brightness of the dual-stage brake lights is controlled as a function of the amount of braking force being used to decelerate the vehicle)
LSZ CONTROL UNIT SCHEMATIC LEGEND
| Key | Explanation | Key | Explanation |
|---|---|---|---|
| 1 | Turn signal (front left) | 2 | Front left: main beam headlights, dipped beam headlights, side lights |
| 3 | Front fog light (left) | 4 | Front fog light (right) |
| 5 | Front right: main beam headlights, dipped beam headlights, side lights | 6 | Turn signal (front right) |
| 7 | Auxiliary turn signal (left) | 8 | Side-marker light (front left) (US version) |
| 9 | Light switch cluster (LSZ) | 10 | Side-marker light (front right) (US version) |
| 11 | Auxiliary turn signal (right) | 12 | Hazard-warning lights switch |
| 13 | Stepper motor controller (SMC) for adaptive headlights | 14 | AHL control unit for adaptive headlights |
| 15 | Instrument cluster control unit (KOMBI), gateway (data interface) between the K bus and PT CAN | 16 | Trailer module (AHM), if fitted |
| 17 | Digital Engine Electronics or Digital Diesel Electronics DME/DDE | 18 | Reversing light (right), license plate light (right) |
| 19 | Rear left: side-marker lamp, turn signal, side lights and brake light | 20 | Rear lights (right), rear fog light (right) |
| 21 | Additional brake light (middle) | 22 | Rear right: side-marker lamp, turn signal, side lights and brake light |
| 23 | Reversing light (left), license plate light (left) | 24 | Reversing light (left), license-plate light (left) |
| 25 | Brake light switch | 26 | Rain-light sensor |
| 27 | Light switch | K bus | Body bus |
| LIN bus | Local bus (Local Interconnect Network) | PT CAN | Powertrain CAN |