Data Wiring Between Engine Control Module

Required special tools and operating instructions





^ VAG1526 A Hand multimeter





^ VAG1594 A test set





^ VAG1598/21 Adapter from VAG1598 A test box

The Engine Control Module (ECM), Transmission Control Module (TCM) and ABS control module are connected together via a Data - Bus. The Data - Bus consists of two data lines, over which information is routed (e.g. signals for engine torque, engine rpm).
- Connect test box VAG1598/21 to wiring harness ABS control module.




Check the following wiring connections for short to positive or ground and open circuit.





- If necessary eliminate open circuit or short.