This bulletin applies to diagnosing anti-lock braking system (ABS) faults on the 2009 Volkswagen Touareg.
When diagnosing MK60 ABS fault codes 00688 (terminal 30 voltage) and 01276 (ABS hydraulic pump), perform voltage drop tests on the two main power and ground wires at the ABS module (pins 1 & 32; 47 & 16).
Perform the voltage drop tests while operating the ABS pump in output diagnosis (03). A loose ground or power supply connector may cause these DTCs. Static voltage tests may not detect the problem.