Lamp Monitoring

Lamp Monitoring


Hot Monitoring







Cold Monitoring







Lamp monitoring on the E46 is a function of the LSZ control module. The following lamps are monitored in both the hot and cold states:
- High/low beams
- Brake lights - left/right
- Turn signal lights
- Tail lights
- Parking lights
- Side marker lights
- License plate lights

Hot monitoring takes place when the lights are switched by monitoring the current flow through the lamp filaments.

Cold monitoring takes place by the LSZ when the lights are switched oft. The LSZ will briefly activate the lighting circuits and check for current flow through the lamps. The lights are not switched on long enough to illuminate the bulbs.

If the LSZ detects a defective bulb, a signal is sent to the instrument cluster and the warning is posted in the Check Control pictogram.

Home Lighting







This convenience feature provides lighting for the driver and passengers to leave the vehicle and enter their house.

The feature is switched on by activating the headlight flasher switch after the lights and ignition are switched off.

The feature is switched oft after the coded time delay or by switching the ignition switch on.

Redundant Storage
The LSZ serves as the redundant storage module in parallel with the instrument cluster.

This includes all data used for vehicle identification which is encoded on the assembly line.

In addition the total mileage and SI data are also stored in the LSZ.

If either the Cluster or LSZ has to be replaced, the data is taken from the remaining module and transferred to the replacement unit. This can only occur ONCE the VIN has been entered into the replacement unit. Once the VIN is entered, the module becomes part of the vehicle and can not be interchanged with another vehicle.