Cologne, Germany – 10 August, 2026 – A Tiguan arrived at a workshop with “excessive parasitic drain” – a larger than normal electrical current that continues to drain a vehicle’s battery, even after the vehicle is turned off and powered down. This caused the battery to drain within 24 hours. 
 

Solution 
 

After searching ALLDATA and finding unedited Technical Service Bulletins (TSBs) related to the main relay – which remained active and caused the radiator fans to start up randomly, despite the ignition switched off – the technician was able to replace the relay. This resolved the issue, and the car worked correctly.  

Without ALLDATA, the technician confirmed that they would not have been able to diagnose and fix the problem. 
 

What do TSBs cover? 
 

TSBs are important pieces of information; they cover engine specifications, dimensions, performance data and repair instructions. Today, ALLDATA provides over 100 million service and repair articles, including TSBs, and more than nine million technical drawings, wiring diagrams and electrical connector views. 

This material is direct and unedited from 44 vehicle manufacturers (VMs) and over 167,000 vehicle. This represents 97% of the European car parc.  

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