Bang & Olufsen BeoLink User Manual page 38

34
Service mode
MASTER LINK
Products with a display feature a service mode in which Master Link faults
can be displayed. Please note that the error reading indicates that the
fault is a system fault, which does not mean that the fault is in the
particular product that is displaying it.
Beolab 3500 and BeoVision Avant are examples of products providing the
service mode feature. Check the service manual for the individual
products to see how these procedures are accessed.
This example of service mode is from Beolab 3500.
ERROR 1: - Address configuration is impossible.
Error during address configuration. No address has been allocated
because too many units are connected to the Master Link.
- Remove all products from Master Link, and connect them again one at
a time until the error code occurs. Disconnect that product from Master
Link.
ERROR 2: - Master Link data pulled low
It is not possible to transmit on Master Link, because it has been pulled
low. The error may occur if there is no Master Link driver circuit, or as a
result of a physical short-circuit on Master Link or in the data transceiver
circuits.
- Disconnect one product from Master Link at a time, and see if it starts
up.
- Reset the faulty product, and check the connection (cable/plug) and
signal path (the data transceiver circuit). See repair tips for the data
transceiver circuit.
ERROR 3: - Master Link data pulled high.
It is not possible to transmit on Master Link, because it has been pulled
high. This error is caused either by the pull-up resistance in the system
having become too small or by an error in the data transceiver circuit.
- Disconnect one product from Master Link at a time, and see if it starts
up.
- Reset the faulty product, check whether the Master Link cable is too
long, and check the signal path (the data transceiver circuit). See repair
tips for the Master Link data transceiver circuit.
ERROR 4: - Data collision on Master Link
The data traffic on Master Link has been excessive, or a product has
jammed and will not receive data telegrams.
- Press the operating sequence again.
- Disconnect one product from Master Link at a time to determine which
product has jammed. Reset the faulty product, and check the Master
Link connection (cable/plug) and signal path (amplifiers in the data
transceiver circuit).
See the service manual for the individual products for further
information.