Initial Inspection and Diagnostic Overview
Functional Description
The Airbag Control Module -J234- is located behind the console on the tunnel. It is equipped with DTC memory. The On Board Diagnostic (OBD) Data Link Connector (DLC) is located under the dash on the drivers side.
The control module detects Diagnostic Trouble Codes (DTC) in the airbag system and stores them in a permanent memory.
DTCs which can be attributed to a temporary open circuit in the wiring or a loose terminal will also be stored. These DTCs will be displayed as sporadic DTCs "SP."
After the ignition is switched on, the Airbag Malfunction Indicator Lamp (MIL) -K75- comes on for about 4 seconds and then goes out again, if the lamp then flashes for a further 15 seconds this signals that the front passenger airbag, is disabled.
- If the Airbag Malfunction Indicator Lamp (MIL) -K75- does not go out again after about 4 seconds, then the voltage supply to the Airbag Control Module -J234- is inoperative. Check DTC memory.
- A DTC is present if the Airbag Malfunction Indicator Lamp (MIL) -K75- lights up again. Check DTC memory.
- If the Airbag Malfunction Indicator Lamp (MIL) -K75- flashes continuously then the Airbag Control Module -J234- must be replaced.
To commence trouble shooting, initiate On Board Diagnostic and retrieve the stored information with the V.A.G 1551/VAS 5051 Scan Tool.
The DTC information displayed is used to refer to a DTC table with notes on possible causes for directed repair measures.
WARNING:
- Only visual check of wiring.
- Do not perform electrical continuity tests or measurements to igniter circuits.
- Only check wiring with ignition switched off.
Check control module version
- Connect Scan Tool. Reading and Clearing Diagnostic Trouble Codes
- Switch on ignition.
- Press button -1- for "Rapid Data Transfer" mode.
Indicated on display
Rapid data transfer HELP
Enter address word XX
- Press buttons -1- and -5- (the address word of the vehicle system to be tested "Airbag" is entered with 15).
Indicated on display
Rapid data transfer Q
15 - Airbag
- Confirm with -Q- button.
Indicated on display (see parts catalog for latest control module version).
8L0 959 655 B AIRBAG VW 3-S V00 ->
Coding 00066 WSC12345
- Top line, part No. of control module, system designation (AIRBAG VW3), version number
- Lower line, code number, dealership number 1)
1) Will be automatically stored in the control module when entering the system.
- Press -> button.
Indicated on display
Rapid data transfer HELP
Select function XX
NOTE:
- If one of the malfunction messages opposite appears in the display, the possible causes can be printed out with the HELP button.
- Ignition must be switched on.
- Malfunctions have occurred at the start of or during the program (external interference?).
- Check diagnostic cable as well as voltage supply and Ground connection.
- After repairing enter the address word 15 for "Airbag" and confirm with the -Q- button.
Indicated in display after entering the address word 15:
Rapid data transfer
Tester sends the address word 15
then the following appears in the display:
Indicated on display (see parts catalog for latest control module version).
8L0 959 655 B AIRBAG VW 3-S V00 ->
Coding 00066 WSC12345
List of selectable functions
01 - Check Control Module Version
02 - Check DTC Memory
03 - Output Diagnostic Test Mode
05 - Erase DTC Memory
06 - End Output
07 - Code Control Module
08 - Read Measured Value Block
NOTE:
- A list of possible functions is printed out after pressing the HELP button.
- Do not select further functions, which can be printed out after pressing the HELP button.
- After the function is completed the V.A.G 1551/VAS 5051 returns to the following start position:
Check DTC Memory
Indicated on display
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -2- (the function "Check DTC Memory" is entered with 02).
Indicated on display
Rapid data transfer Q
02 - Check DTC Memory
- Press Print button.
- Confirm with -Q- button.
The number of stored DTCs appears in the display.
X DTCs recognized!
The stored DTCs are displayed and printed out one after the other.
- Enter DTC table at DTC printed out and repair.
If "No DTC recognized" is displayed the program will return to the initial position after pressing the -> button.
No DTC recognized! ->
Indicated on display
Rapid data transfer HELP
Select function XX
If something else is displayed:
See Scan Tool operating instructions
- End output (function 06).
- Switch off ignition and separate diagnostic connections.
NOTE:
If a DTC is recognized:
- Repair malfunction.
- Erase DTC memory (function 05).
- Check DTC memory again (function 02).
Erase DTC Memory
Test requirements:
- DTCs are repaired
- DTC memory checked again
Indicated on display
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -5- (the function "Erase DTC Memory" is entered with 05).
Indicated on display
Rapid data transfer Q
05 - Erase DTC Memory
- Confirm with -Q- button.
Indicated on display
Rapid data transfer ->
DTC Memory is erased!
- Press -> button.
Indicated on display
Rapid data transfer HELP
Select function XX
NOTE:
- If this appears in the display, the test sequence is inoperative.
- Adhere strictly to test sequence; first check DTC memory, then erase memory.
End output
- Press buttons -0- and -6- to end the output.
Indicated on display
Rapid data transfer Q
06 - End output
- Confirm with -Q- button.
Indicated on display
Rapid data transfer HELP
Enter address word XX
- Switch off ignition.
- Disconnect connector to V.A.G 1551 A/AS 5051 Scan Tool.