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Mode 7



Data Output with a Scan Tool

The output of data relevant to OBD from the control modules was stipulated by law for the USA. It is described in SAE J 1979.

Data output is subdivided into different modes.


Mode 7

Output of test results of continuous tests. (Output of suspected faults)

The data sets in the modes are referred to as Parameter Identification (PID).

After being stimulated by a generic scan tool, all systems relevant to OBD log on with their address. In vehicles with ME 7.2 this is the DME with the address $11 and in Tiptronic vehicles it is the transmission control module with the address $1A.

NOTE: The $ symbol means that a hexadecimal number is involved.

When the control module provides data, it also states the mode, the PID number and the address of the control module.

Example:
Mode 41Pid$01 Adr$11
Engine control
No. of faults: 0
MIL commanded OFF

Data output takes place
with Mode 41 in Mode 1,
with Mode 42 in Mode 2,
with Mode 43 in Mode 3 etc.

Mode 7
The Diagnostic Trouble Codes of all non-shedded, officially relevant* faults are displayed in Mode 7. This mode has the same structure as Mode 3.

* Faults which switch on the Check Engine warning light