With Manufacturer's Scan Tool

Voltage supply to Engine Control Module (ECM), checking

Required special tools and test equipment
- VAG 1551 or VAG 1552 Scan Tool (ST) with VAG 155I/3 adapter cable
- VAG 1598/22 test box
- Multimeter US 1119 (Fluke 83 or equivalent)
- VW 1594 connector test kit
- Wiring diagram

Checking
- Connect VAG 1551 or VAG 1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with ignition switched on). Connecting VAG 1551 Scan Tool

Indicated on display


Rapid data transfer HELP
Select function XX


- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display


Read Measuring Value Block HELP
Input display group number XXX


- Press buttons -0-, -0- and -4- to input display group number 4 (004), and press -Q- button to confirm input.

Indicated on display (1-4 = display fields)


Read Measuring Value Block 4 ->
1 2 3 4


- Check battery positive voltage (B+) in display field 2.

Display Group 4:

If displayed value is OK (as specified):
- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.

Evaluation of display group 4

Display Group 4:

Checking voltage supply at terminal 30

- Switch ignition off.
- Connect VAG 1598/22 test box to ECM harness connector. Connecting VAG 1598/22 Test Box
- Connect multimeter US 1119 (Fluke 83 or equivalent) between ECM/test box sockets 2 (Ground) and 3 (B+), using adapter cables from VW 1594 connector test kit.
Specified value: 10-14.5 volts

If voltage is NOT OK:
- Check wiring according to applicable wiring diagram.


Checking voltage supply at terminal 15
- Switch ignition off.
- Connect VAG 1598/22 test box to ECM harness connector. Connecting VAG 1598/22 Test Box
- Connect multimeter between ECM/test box sockets 1 (B+) and 2 (Ground), using adapter cables from VW 1594 connector test kit.
- Switch ignition on, and check voltage.
Specified value: 10-14.5 volts

If voltage is NOT OK:
- Check wiring according to applicable wiring diagram.
- Check readiness code.If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code. Audi Drive Cycle/Readiness Code