BMW F33 STMR Failed Initialisation 2020-08-

BMW F33 HeadLight Module_right
This Job is to encode a used STMR module and initialized it

Left headlight driver module and right headlight driver module
Left headlight driver module (STML) and right headlight driver module (STMR)
The headlight driver module is fitted as a printed circuit board in the LED headlight. The headlight driver module evaluates the signals sent from the footwell module (FRM) via the LIN bus and K-CAN3. In this process, the headlight driver module assumes control of the following lighting functions of the LED headlight:

Side lights
Daytime driving lights
Side marker light
Turn indicator
Positioning light
Besides the lighting functions, the headlight driver module also controls the stepper motors for headlight beam throw adjustment and for the adaptive headlight.

Functional description
The footwell module (FRM) is the master control unit for the exterior lights. That means: All lighting functions are controlled by the footwell module (FRM).

When prompted by the footwell module (FRM) the headlight driver module controls the stepper motors for headlight beam height adjustment and for the adaptive headlights. The footwell module (FRM) outputs the prompt in the form of a message on the LIN bus.

When prompted by the footwell module (FRM) the headlight driver module controls the relevant lighting functions. The footwell module (FRM) sends the request in the form of a message on the K-CAN2. The central gateway module (ZGM) forwards the message on the K-CAN3 to the left headlight driver module (STML) and to the right headlight driver module (STMR).

The following graphic shows the left headlight driver module (STML) on the F01 with LED headlight by way of example.


Item Explanation Item Explanation
1 Left headlight, view from rear 2 Left headlight driver module (STML)
3 Printed circuit board
Structure and inner electrical connection
The two headlight driver modules are of the same design, but are divided by means of pin coding into a left headlight driver module (STML) and a right headlight driver module (STMR). In the event of a replacement, the corresponding headlight driver module must be encoded.

The headlight driver module (STML or STMR) is a bus user on the K-CAN3. Furthermore, the headlight driver module is connected via a LIN bus to the footwell module (FRM).

The rear power distribution box supplies the two headlight driver modules (STML and STMR) with terminal 30F.


Item Explanation Item Explanation
1 Left headlight driver module (STML) or right headlight driver module (STMR)
Pin assignments

The graphic above shows only the supply and bus connection. The current pin assignment is recorded on the wiring diagrams in the ISTA diagnosis system (Integrated Service Technical Application). Click on the component code in the wiring diagram to activate the "Installation location" and "Pin assignment" tabs.

Nominal values
Observe the following setpoint values for the left headlight driver module (STML) or right headlight driver module (STMR):
Variable Value
Supply voltage 9 to 16 volts
Temperature range -40 to 105 deg C
Diagnosis instructions
Failure of the component
In the event of a failure in communication with the left headlight driver module (STML) or right headlight driver module (STMR), carry out the standard tests (global test procedure). If there is an internal control unit fault, the following behaviour is to be expected:

Fault code entry in the left headlight driver module (STML) or right headlight driver module (STMR)
Check Control message in the instrument panel