With the use of a universal or 'generic'
scan tool connected to the DLC
(Diagnostic Link Connector), diagnostic
trouble codes (DTCs) can be obtained,
along with the conditions associated
with the illumination of the engine
service light. Using a more advanced or
BMW-dedicated scan tool, additional
'proprietary' information is normally
available.
Scan tool and scan tool display
Owing to the advanced nature of OBD
II adaptive strategies, all diagnostics
need to start with a scan tool. The
aftermarket scan tools can be
connected to either the 16-pin OBD II
Data Link Connector (DLC) or the BMW
20-pin DLC in the engine compartment.
Data from the OBD II DLC may be
limited, depending on scan tool and
vehicle.
OBD II standards mandate that the
16-pin DLC must be located within
three (3) feet of the driver and must not
require any tools to be exposed. The
communication protocol used by BMW
is ISO 9141.
Starting with June 2000 production, the
20-pin BMW diagnostic port (
Data Link
Connector
or
DLC
) which was
previously located in the engine
compartment has been deleted. All
diagnostic, coding and programming
functions are incorporated into the
OBD II
diagnostic port, located under
left side of dashboard.
Note:
On cars built up 06-2000: when
accessing emissions related DTCs
through the 16-pin OBD II DLC, the
BMW 20-pin DLC cap must be
On-Board Diagnostics
http://ebahn.bentleypublishers.com/BMW/3/E46/Repair%20Manuals/8...
5 of 11
2/25/2009 11:22 PM
Summary of Contents for 1999-2005 M3
Page 1: ......