2009 VW Jetta Sportswagon P0720 Code: Output Speed Sensor Issue and DIY Fix Guide
Hi everyone, first-time poster here. My 2009 Volkswagen Jetta Sportwagons has recently started triggering the check engine light, which decodes to P0720 — indicating a fault in the output speed sensor circuit. This sensor is part of the automatic transmission system and monitors gear position and vehicle speed for proper transmission operation. I've already cleared the code twice, but it returns quickly after, suggesting an underlying issue rather than a temporary glitch. I'm trying to figure out whether this can be fixed myself or if I should take it to an independent transmission specialist. The sensor is typically located near the rear of the transmission, accessible from underneath the vehicle. While some online guides suggest checking for loose wiring or corrosion, others recommend replacing the sensor if the readings are inconsistent. Any practical advice — especially on where to find the sensor, how to test it, or whether a DIY repair is safe and effective? I'm looking for cost-effective solutions before heading to a shop. Thanks in advance! John Alameda, CA
This is a do-it-yourself (DIY) repair feasible for most car owners with basic mechanical skills. If you're comfortable working under the vehicle and have access to a multimeter or diagnostic tool, inspecting the wiring harness and sensor connections can help identify issues. If problems persist after checking the physical components, replacing the output speed sensor is often effective. For those who prefer professional help, an independent transmission specialist with experience in VW models would be a reliable option.