ODI opened this investigation after receiving reports that both headlights would go out, or extinguish while driving.the subject vehicles are equipped with high intensity discharge (hid) headlamps that operate on independent lamps and ECU's (electronic control units) for each headlight, meaning that each headlight runs independently of the other, and a failure in one lamp or ECU does not necessarily result in a failure of the other.during the investigation, a random sample of forty consumers was contacted by ODI in a telephone survey to verify their experiences.the consumers stated in complaints to Toyota that both headlights failed at the same time.ODI discovered through talking with these complainants that in fact one headlight would begin to flicker and then cut off.the other headlight would still be operational.in a few cases where no action was taken, some complainants stated that after a few months both headlamps would begin to fail resulting in no headlights; however none reported that both lamps failed simultaneously.complainants also stated that they could toggle the headlamp switch on and off to temporarily restore lighting when this condition occurred, even in cases were both headlamps were extinguished.the results of this survey are largely consistent with ODI's assessment of the reports and warranty data.Toyota submitted in response to ODI's information request letter that, generally speaking, only one lamp failed at a time, and that toggling the switch restored the lamp.Toyota requested a meeting with ODI and on August 6, 2009, presented their assessment of headlamp failure.Toyota confirmed that a headlamp could extinguish while driving due to a bulb failure, and that it could be temporarily restored by turning the headlight switch on and off, and that simultaneous failure of both headlamps was rare and unlikely.Toyota also briefly discussed their intention to conduct a customer service campaign to address consumer dissatisfaction with hid bulb failures.since there is still one headlight operating when the other one cuts off, there is still lighting available to get the vehicle to a repair facility.thus, a safety defect trend has not been identified at this time and further use of Agency resources does not appear to be warranted.accordingly this investigation is closed.the closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist.the Agency will take further action if warranted by the circumstances.
