Vehicle Overspeed Condition Detected
The P0297 code indicates that the Engine Control Module (ECM) has detected the vehicle exceeding a predetermined speed threshold, typically set by the manufacturer. This condition is often triggered when the vehicle's speed exceeds a specific limit, such as 120 mph, for a sustained period. The ECM monitors wheel speed sensors and compares the actual speed to the programmed limit. If the limit is exceeded, the code is set and may trigger a warning light or reduce engine power.
01. Most Common Causes
- Driving at excessive speeds for an extended duration
- Faulty wheel speed sensor or wiring
- Mismatched tire sizes affecting speed calculation
- ECM software calibration error
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or limp mode
- Speedometer reading inaccurately
- Cruise control may be disabled
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.
Step 2: Inspect wheel speed sensors and wiring for damage or corrosion.
Step 3: Verify tire sizes are correct and match manufacturer specifications.
Step 4: Check for any aftermarket modifications that could affect speed readings.
Step 5: Clear the code and test drive to see if it returns under normal driving conditions.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is generally safe to drive at legal speeds, but the vehicle may enter limp mode to limit speed. If the code was triggered by a sensor fault, it could affect other systems. Have it diagnosed promptly.
How much does it cost to fix?▼
If the cause is simply overspeeding, clearing the code is free. If a sensor needs replacement, expect $50-$150 for parts and labor.