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Troubleshooting
BR/BD 75/140 R, BR/BD 90/140 R
New Unit Information 03.2004
Unit does not operate
Instrument panel, view from above
2
2
Insert/Check/Replace central battery
connector (X1)
Set multimeter to Volt setting and check the cen-
tral battery connector (1), replace any defective
parts.
Check the connection cable (3)
– Disconnect the positive battery post
– : Disconnect the connection ca-
ble on the control panel printed circuit board
and check for continuity
– : Pull off the connection cable on
the main control printed circuit board (terminal
strip X205) and check for continuity (auxiliary
contact S32 in central connector lower sec-
tion).
– If no continuity is present check the connec-
tion cable’s in the lower section of the central
connection plug (2).
Check/replace the key switch (S0)
– Unplug the upper section of the central con-
nection plug (1).
– Set the multimeter to the ohm measuring ran-
ge.
– Turn the key switch to the “0” position.
– Pull a connection cable off the key switch.
– Carry out the resistance measurement on the
key switch.
When switched off the key switch must display
a high-ohm (high-resistance) value.
When switched on the key switch must display
a low-ohm (low-resistance) value.
– If necessary replace the key switch.
Check/Replace fuse F1
Check fuse F1, replace defective fuse. The fuse
is located on the main control printed circuit board.
Check key switch (S0) (illustration of NEW control
panel printed circuit board)
Central battery connector (X1)
Ω
1
Upper section of central connector plug
2
Lower section of central connector plug
3
Connection cable (auxiliary contact S32)
4
Key switch (S0)
1
3
ORIGINAL
REVISED