With Manufacturer's Scan Tool

Control module voltage supply, checking

Test requirements:

- Fuse for engine control module OK
- Battery voltage at least 11 V
- Generator OK


- Connect Vehicle Diagnostic, Testing and Information System VAS5051 or VAG 1551 Scan Tool and select engine electronics control module by entering address word "01". When doing this the engine must be at idle.

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select function "Read Measuring Value Block" and confirm entry with -Q- button.

Indicated on display

Read Measuring Value Block
Input display group number XXX

- Press buttons -0-, -0- and -4- to select "display group number 004" and confirm entry with -Q- button.

Indicated on display

Read Measuring Value Block 4 ->
1 2 3 4

- Check display readout for battery voltage in display field 2.

Evaluation Display Group 4

Checking voltage supply from terminals 15 and 30

- Connect VAG 1598/31 test box to wiring harness for engine control module. DO NOT connect to engine control module itself, Connecting VAG 1598/31 Test Box

- Connect VAG 1526 multimeter (voltage measurement range) to following sockets on the test box:


If the specifications are not obtained:
- Check wiring.
- Display readiness code, Readiness Code Reading . If DTC memory was erased generate readiness code, Readiness Code, Generating