When buying a used car, it’s crucial to know if the check engine light has been recently reset. A cleared check engine light could be hiding underlying problems. The BlueDriver OBD2 diagnostic scan tool can help you uncover potential issues. This article explains how BlueDriver helps determine if check engine codes have been recently erased.
Using BlueDriver to Detect Erased Codes
BlueDriver utilizes two primary methods to identify recently cleared codes: MIL Status and Smog Check data. These features provide valuable insights into the vehicle’s history and potential hidden problems.
MIL Status: Deciphering the Check Engine Light
The MIL (Malfunction Indicator Lamp) Status page in the BlueDriver app indicates whether the check engine light is currently on or off. More importantly, if the vehicle supports it, BlueDriver can display:
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Warm-up Cycles Since DTCs Cleared: This counts the number of times the engine has warmed up significantly (coolant temperature rising at least 40°F and reaching a minimum of 160°F for gasoline engines, 140°F for diesel engines) since the last code clearing. Multiple warm-up cycles with no recurring codes suggest a potentially resolved issue. However, few or no warm-ups might raise suspicion.
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Distance Traveled Since DTCs Cleared: This reveals the total distance driven since codes were last cleared. A short distance combined with a cleared check engine light could indicate an attempt to mask a problem.
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Engine Run Time Since DTCs Cleared: This shows the accumulated engine running time since the last code clearing. Similar to distance traveled, a low engine run time after a reset could be a red flag.
Smog Check: Uncovering Incomplete Tests
If the vehicle doesn’t support the detailed MIL Status data points, the Smog Check feature in BlueDriver offers another way to detect recently cleared codes.
Clearing codes resets all vehicle emissions tests to a “not complete” status. Driving under various conditions (city, highway) allows the vehicle’s computer (ECM) to gather data and complete these tests. Multiple “not complete” tests under the Smog Check section strongly suggest a recent code clearing. This is because the ECM hasn’t had enough time to re-evaluate the vehicle’s emissions systems.
Conclusion: BlueDriver empowers you
By using the MIL Status and Smog Check features, BlueDriver empowers you to make informed decisions when purchasing a used vehicle. While a cleared check engine light doesn’t automatically indicate a problem, it warrants further investigation. BlueDriver provides the data you need to assess the situation and avoid potentially costly repairs down the road. Using BlueDriver’s comprehensive diagnostic capabilities can help ensure you’re buying a reliable vehicle.
