EMC measures E61 and E91

Measures to increase electromagnetic compatibility

For certain known fault profiles, design measures have already been implemented in production.

Check these design measures in the event of EMC faults:

  1. Earth strap on the luggage compartment lid
    Fault profile with effect:
    corrosion means that the earth connection between the luggage compartment lid and body is lost. This means that the luggage compartment lid oscillates and is electrically undefined.
    The reception deteriorates 2 to 3 years after production of the vehicle.
  2. Suppressor filter for the additional brake light
    Fault profile with effect:
    in the wiring harness, EMC faults occur between the additional brake light, including supply lead, and the AM antenna.
    The reception deteriorates on braking.
  3. Cable choke
    Fault profile with effect:
    the cable choke sets the screen of the coaxial line between the head unit and antenna diversity to ground.
    In areas with poor transmission power, AM reception is disrupted or is lost at an earlier stage.

EMC measures E61:

GR_FB6507009

 

Index

Explanation

Index

Explanation

1

Earth strap on the luggage compartment lid:
integrated in the luggage compartment hinge

2

Suppressor filter for the additional brake light:
secured above the D-pillar, under the headlining

3

Cable choke:
Secured above the D-pillar under the headlining

 

 

EMC measures E91:

 

GR_FB6507008

Index

Explanation

Index

Explanation

1

Earth strap on the luggage compartment lid:
integrated in the luggage compartment hinge

2

Suppressor filter for the additional brake light:
secured above the D-pillar, under the headlining

3

Cable choke:
Secured above the D-pillar under the headlining

 

 


Notes for Service department

Diagnosis instructions

The antenna diagnosis runs as follows:

The self-diagnosis of the antenna diversity is triggered in the test module of the BMW diagnosis system. The self-diagnosis includes a check of the antenna inputs on the basis of a current measurement (direct current). If a fault is found, the antenna diagnosis aborts after the self-diagnosis.

If the self-diagnosis has a positive result, the FM antennas are specifically activated and evaluated with regard to field strength (check of the antennas).

Diagram of antenna diagnosis:

GR_FB8407006

Index

Explanation

Index

Explanation

1

Normal receive mode

(t1 to t2: diversity 2.5 Volt)

2

Self-diagnosis

3

Test of the antennas

(t6 to t8: switching pulse 8.5 Volt)

4

Self-diagnosis has positive result

(t2 to t5: 5 Volt)

5

Self-diagnosis has negative result: Fault detected

(t3 to t4: 0 Volt)

6

Actions triggered by the antenna diagnosis

(t9: AM 0 Volt


No liability can be accepted for printing or other faults. Subject to changes of a technical nature