Buying a used car can be a frustrating experience. It can be even more frustrating when the check engine light comes on shortly after delivery. Many dealers will fix problems with the cars, but some dealerships will attempt to avoid their responsibilities by tampering with a car's check engine light. This is a serious type of Auto Dealer Fraud.
A vehicle's check engine light will come on when the vehicle's computer detects a Diagnostic Trouble Code. The problem can be as simple as a loose gas cap or as serious as a defective engine that requires replacement. Frequently, the cause may be a defective catalytic converter or oxygen sensor. A mechanic can determine the reason for the light by using a scanning tool to determine the diagnostic code. This is an important step in diagnosing the problem with the car.
Car dealers who sell newer model used cars (typically less than seven years old) are required to provide a warranty under Connecticut law. Many times dealerships will give a warranty for older models as well. Warranties usually require the dealership to make necessary engine repairs during the warranty period, which is typically (but not always) one or two months in duration.
Many dealerships will try to avoid repairs by simply re-setting the check engine light without fixing the problem. However, vehicles are designed to re-display the light after a few days of driving time, and assertive consumers will return the car and press the dealer to diagnose and fix the problem.
We have seen several instances where a dealership will attempt to avoid repairs by tampering with the check engine light. Some dealerships place black tape between the bulb and the panel so that the light cannot be seen. Other dealers may remove the bulb. In these instances, consumers might discover the fraud when they notice that the light does not briefly come on when the engine is first turned on.
We had one case where a dealership re-wired the vehicle so that the light would briefly illuminate when the car engine starts but would not display when a code is detected. The consumer discovered the problem when an independent mechanic observed that the computer was displaying codes but the light was not turning on. A check of the vehicle's wiring confirmed the tampering.
Consumers can protect themselves from unscrupulous dealerships by having their car computer checked by an auto parts store; many will scan vehicle computers at no charge. Consumers can learn for themslves what codes are being reported by the computer and can later confirm that the codes are no longer there after a repair attempt. Consumers should also periodically check to confirm that all of their dashboard lights briefly illuminate upon start-up.
For more information on how to avoid used car hassles, check out our free webinar.