VW Jetta Oil Pressure Warning Signals Sensor Failure

I had a very similar issue with my 2015 VW Passat Hybrid last winter. Having some experience with basic car maintenance, I initially thought I could diagnose it myself using a standard OBD scanner. The oil temperature sensor readings were inconsistent, causing the oil pressure warning to flash intermittently. The engine sensor was showing erratic values during car diagnostics. After monitoring the oil gauge for a few days, I noticed the readings would fluctuate especially during cold starts. Took it to a workshop where they found a faulty connection between the temperature sensor and its wiring harness. The total repair came to 95€, which included checking all nearby connections and replacing some corroded pins. The key was catching it early, these sensor issues can sometimes mask more serious problems if left unchecked. Since the repair, all warning lights have stayed off and the oil pressure readings remain stable. Before suggesting specific fixes, could you share: Current mileage on your Jetta? Does the warning appear more frequently during cold starts? Have you noticed any actual oil pressure or temperature issues? Are there any other warning lights appearing simultaneously? This information would help determine if your situation matches what I experienced.

Thanks for sharing your experience. My Jetta only has 12958km since the latest service. To add to your observations, I notice the warning appears out of nowhere, not just during cold starts. The engine temperature readings seem normal when I check them through the infotainment system, but the oil pressure warning persists. The automotive sensor diagnostics do point toward an electrical issue rather than a mechanical problem. After reading about your experience with the wiring harness, I think getting a professional inspection of the temp sensor connections would be a smart first step. The oil gauge itself shows normal readings right before the warning triggers, which seems to support the theory of a sensor malfunction rather than an actual oil pressure problem.

Thanks for those details, that low mileage since service definitely points more toward an electrical issue rather than mechanical wear. Your symptoms align almost exactly with what I experienced, especially the unusual warning triggers despite normal oil gauge readings. After my repair, I learned these sensor systems are quite interconnected. The engine sensor can report false oil pressure warnings even when the actual pressure is fine. In my case, the car diagnostics showed normal readings right until the warning triggered, just like yours. One thing I noticed before the full repair was that gently wiggling the wiring near the oil temperature sensor would sometimes temporarily clear the warning. This helped the workshop pinpoint the connection issue faster. You might want to have them specifically check: Wiring harness connections near the sensor, Ground points for corrosion, Pin fit in the sensor connector The repair should be fairly straightforward and likely in the same cost range as mine (around 100€). Since getting it fixed, my oil pressure warnings completely stopped and all sensor readings have remained stable. Just make sure to mention the unusual timing of the warnings to the workshop, that detail helped differentiate my wiring issue from an actual sensor failure.

Thanks for the detailed feedback and suggestions. I just checked, looking at my maintenance records, the Jetta has 12958km since last service. The unusual warning pattern definitely matches what you described. The fact that my oil gauge readings are normal until the warning suddenly triggers does make me feel better about it being a sensor or wiring issue rather than an actual oil pressure problem. Your experience with the wiring harness connection seems very similar to my symptoms. I made an appointment with my regular workshop for next week. Based on your insights, I asked them to specifically inspect the temperature sensor wiring and connections. The service advisor mentioned they regularly see these kinds of electrical gremlins with the oil pressure monitoring system. I feel more confident now that this is likely a straightforward fix involving the sensor connections rather than a major mechanical issue. Will keep monitoring the warnings until the appointment, but at least I understand better what we're likely dealing with. The cost estimate they provided was also in line with what you paid for your repair.