* Underlying Engine Problem Affecting Traction Control: The most likely scenario is a malfunction within the engine's systems that's causing the car's computer to disable the traction control as a safety precaution. This could be anything from a faulty sensor (like the mass airflow sensor, crankshaft position sensor, or throttle position sensor) to a more serious issue like a problem with the engine's ignition system or fuel delivery. The check engine light will store a diagnostic trouble code (DTC) that will help pinpoint the problem.
* Wheel Speed Sensor Issue: A faulty wheel speed sensor can affect both the traction control system (which relies on wheel speed data to function) and might trigger a check engine light indirectly. The computer detects an inconsistency in wheel speed data and flags it.
* Transmission Problems (Less Likely): In some cases, transmission issues can also trigger both lights. However, this is less common than sensor or engine problems.
* Brake System Issues (Remote Possibility): While less probable, severe brake system problems *could* theoretically affect both. This would likely involve a sensor related to wheel speed or ABS.
What You Should Do:
1. Don't ignore it: Driving with these lights on could lead to reduced performance, poor handling, and potentially unsafe driving conditions.
2. Get a Diagnostic Trouble Code (DTC) Scan: The most important step is to have a mechanic (or use an OBD-II scanner) read the DTCs stored by the car's computer. This will give you a much more specific idea of what's causing the problem. Auto parts stores often offer free DTC scans.
3. Address the Underlying Problem: Once the code is obtained, you (or your mechanic) can identify and repair the specific issue causing the malfunction. Attempting to fix the problem without knowing the DTC is like trying to find a needle in a haystack.
In short, seeing both lights on together means you need professional diagnosis. Don't attempt major repairs yourself unless you have significant automotive experience. The DTC is key to an accurate and efficient repair.
