Symptom: Jetta GiF car after the rain can not start the engine, with the fault detector can not communicate with the engine control unit.
     Cause: The engine is installed on the left side of the tank. As the drain hole of the sump is blocked by the dirt, the water can not be discharged when it is raining or car washing, resulting in the wetting of the engine control unit, resulting in poor or short circuit of the engine control unit , Damage, which led to the engine electronic control system can not work properly.
     Troubleshooting: Disconnect the engine control unit plug and dry it with compressed air. If the fault can not be eliminated, it is recommended to replace the engine control unit.