Scan Tool Connecting and Initial Checks
VAG 1551 Scan Tool (ST), VAS 5051 Vehicle Diagnostic Testing And Information System, Connecting And Selecting Functions
Requirements
- All fuses OK per wiring diagram
- Battery positive voltage (B+) OK
- Ignition off
- Connect tester with adapter cable to Data Link Connector (DLC), located under instrument panel to left of steering wheel.
- VAS 5051/1552: Use adapter cable VAS 5051/1
- VAG 1551: Use adapter cable VAG 1551/3
NOTE:
- If test equipment is to be used during a road test then read safety precautions.
- The following description only covers the procedure for performing OBD VAG 1551 Scan Tool.
- If using VAS5051 or VAG 1552, follow the operating instructions supplied with the equipment.
Indicated on display1)
V.A.G - ON BOARD DIAGNOSTIC HELP
1 - Rapid data transfer
2 - Blink code output
1) Operating modes 1 and 2 are displayed alternately
NOTE:
- If nothing appears on the display of the VAG 1551 Scan Tool (ST), check the Data Link Connector (DLC) wiring.
- Additional operating information can be displayed by pressing the HELP button on the VAG 1551 scan tool.
- The -> button is used to advance through the program sequence.
- The PRINT button is used to switch on the printer (the indicator lamp in the button lights up).
- DTC memory cannot be erased until it has been checked.
- Switch ignition on and/or start engine (engine speed less than 3000 RPM).
- Switch on compressor (press AUTO button on A/C control head -E87-).
- Press button -1- to select "Rapid data transfer" operating mode 1.
NOTE: To check the speed signal (in "Read Measuring Value Block" function 08), move the vehicle a few meters (or yards) at walking speed before starting the OBD program.
Indicated on display
Rapid data transfer HELP
Insert address word XX
- Press buttons -0- and -8- to insert "AC/Heating Electronics" address word 08.
Indicated on display
Rapid data transfer Q
08 - AC/Heating Electronics
- Press -Q-button to confirm input.
Indicated on display
Rapid data transfer
Scan Tool sends address word 08
After a short delay, the control module identification (version), coding and dealership number (where the control module was coded) are displayed ("Klimavollautomat" = fully automatic air conditioner).
8N0 820 043 X TT Klimavollautomat DXX
Code XXXXX WSC ZZZZZ
Control module identification and application (depending on the vehicle equipment and coding).
NOTE:
As a running change in production, A/C control heads -E87- with part numbers including index letters "A" and onward may be installed. These units differ from previous ones (without index letter) as follows:
- On vehicles equipped with immobilizer, allocation of ignition key is recognized (transmitted by instrument cluster) and is displayed in read measuring value block, display group 009 (function 08). Reading
- The last four compressor cut-out conditions in effect for more than 20 seconds are stored and displayed in read measuring value block, display group 011 Reading
Coding Table:
NOTE:
- WSC ZZZZZ is the dealership number of the VAG 1551 scan tool last used to perform the coding procedure.
- DXX is the software version installed in the A/C control head -E87-. It is irrelevant for the purposes of dealership repairs.
- Coding the A/C control head -E87-
List of functions
01 - Check Control Module Versions
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
Only the functions listed above can be used for the "AC/Heating Electronics" OBD program.
- Press -> button.
Indicated on display
Rapid data transfer HELP
Select function XX
NOTE:
- A list of the possible functions is printed out after pressing the HELP button.
- After pressing the -> button, the VAG 1551 returns to the starting position.
If one of the following DTC messages is displayed:
Indicated on display
Rapid data transfer HELP
Control module does not answer
or
Indicated on display
Rapid data transfer HELP
K wire not switching to B+
- Press HELP button to print out list of possible causes.
- Check wiring to Data Link Connector (DLC) according to wiring diagram.
Rapid data transfer ->
No signal from control module
If this display appears at the beginning of or during the OBD program, malfunctions have occurred and data transfer is no longer possible between the VAG 1551 Scan Tool (ST) and the A/C control head -E87-.
Rapid data transfer ->
Error in communication link
- Check wiring to DLC.
- After repairing possible causes of the malfunction, press buttons -0-and -8- to insert "AC/Heating Electronics" address word 08.
- Press -Q-button to confirm input.
Indicated on display
Rapid data transfer
Scan Tool sends address word 08
The control module identification (version), coding and dealership number (where the control module was coded) are displayed ("Klimavollautomat" = fully automatic air conditioner).
4B0820043XA6Klimavollautomat DXX ->
Code XXXXX WSC ZZZZZ
- Press -> button.
Indicated on display
Rapid data transfer HELP
Select function XX