Volkswagen Passat 1995 Official Factory Repair Manual page 1745

On Board Diagnostic (OBD II)
http://ebahn.bentleypublishers.com/vw/servlet/Display?action=Goto&type=repair&id=VW.B4.FU07.01.1
Engine Control Module (ECM) functions
Note:
The ECM is equipped with various functions.
Some functions can be carried out with ignition
switched on or with engine running. The following
table details the prerequisites for selecting the
individual functions.
Function
performable with
02 Check DTC
Memory
03 Output
Diagnostic Test
Mode
04 Basic Setting
05 Erase DTC
Memory
06 End Output
07 Code Control
Module
08 Read Measuring
Value Block
1)
Must be performed after the following work:
replacement of Engine Control Module (ECM),
throttle valve control module or engine
2)
Only possible when coolant temperature is
above 80 C (176 F). Prior to this, function 04 is
blocked.
3)
Must be performed when checking idle speed.
Page 6 of 6
Ignition Engine
switched on idling
Yes Yes
Yes No
1) 2)3)
Yes Yes
Yes Yes
Yes Yes
Yes No
Yes Yes
01-6
12/6/2004