PE18004 · PE
ELECTRICAL SYSTEM Investigation
On April 23, 2018, the Office of Defects Investigation (ODI) opened this Preliminary Evaluation (PE18-004) to investigate certain alleged defects affecting the Powernet Distribution Box (PNDB) and associated wiring on certain model year (MY) 2011-2016 Freightliner Cascadia (P3 platform) truck tractors that may result in disruption or loss of electrical power to the PNDB itself and other electrical circuits, thermal events, and/or vehicle fires.On May 7, 2018, ODI sent an Information Request (IR) letter to Daimler Trucks North America LLC (DTNA). On June 19, 2018, ODI received an IR response from DTNA that included vehicle production, consumer complaint, field report, warranty, manufacturer actions, changes and other data related to the alleged defects. On April 8, 2019, ODI received a supplemental IR response from DTNA that included their assessment of the alleged defects. Furthermore, ODI engaged in discussions with the manufacturer about the alleged defects on multiple occasions during the course of this investigation. ODI analysis of all available data indicates there is not an apparent defect trend. The most recent field report data reviewed was from 2017Q1 and the most recent complaint data was received by ODI in 2019Q1. The complaint rate is low. Most warranty claims occurred early in the vehicles' service life, and with the newest of the subject vehicles being over four years old, they are all now beyond that point. The warranty claim rates for loose input or output terminals (0.16%), loose fuses (0.25%), PNDB power (B+) supply cable corrosion or improper PNDB power (B+) supply cable routing and/ or securement (0.00%) are all low.The most serious consequence in the warranty claim data alleged engine shutoff with a vehicle in motion. While some vehicles did experience a loss of electrical power resulting in loss of motive power with no immediate restart capability, the bulk of the warranty claims were for vehicles equipped with an optional cab power disconnect switch solenoid with an automatic reset feature that may exhibit a brief, intermittent loss of power. If the input and output voltages differ by an unacceptable amount, potentially due to foreign object debris or corrosion on the solenoid's contacts, the PNDB senses the difference and enters an auto-reset mode in an attempt to correct the condition. The internal contacts open for one second, stopping the flow of electricity, and then close, restoring the flow for two seconds. This cycle is repeated for up to five times; after a maximum of thirteen seconds, the PNDB defaults to the on position and electrical power is restored. This condition exhibits a transient loss of power but it does not cause any permanent engine disablement. As a precaution, the solenoid-equipped PNDB part was modified in August 2017 to eliminate the auto-reset feature. Since 2010, there has been only 1 report of vehicle fire and zero reports of crash, injury or death. Accordingly, this investigation is closed. The closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists. The agency reserves the right to take further action if warranted by the circumstances.
RQ17008 · RQ
EQUIPMENT:RECREATIONAL VEHICLE/TRAILER Investigation
On February 26, 2016, Bergstrom Inc. notified NHTSA of a safety defect in approximately 10,819 of its ParkSmart auxiliary electrical temperature management units. These units were installed on Freightliner Cascadia Class 8 trucks that may overheat due to high resistance, resulting in possible fires. One of the contributing factors which led to this recall was a plastic vented cap covering the compressor connectors allowing increased flow of air to the overheated connectors, which increased the risk of a fire.ParkSmart units equipped with non-vented caps, according to Bergstrom, were not affected. See Bergstrom recall 16E-017.On March 7, 2016, Daimler Trucks North America (DTNA), the parent company of Freightliner, filed its corresponding defect decision as to the impacted Freightliner trucks.DTNA identified 8,865 model year 2015-2016 Freightliner Cascadia trucks installed with the ParkSmart units.On September 18, 2017, the Recall Management Division (RMD), opened this investigation to resolve the discrepancy between the larger number of units Bergstrom recalled with the smaller number of trucks DTNA identified as impacted, and to pursue additional recall actions as needed. RMD issued an information request to DTNA on Oct. 26, 2017 inquiring about the discrepancy, as well as field experience information.DTNA filed several responses of different dates that provided shipping and distribution information as well as field reports.DTNA explained that their recalled population was comprised only of vehicles they had produced for the U.S. market.They identified that 1,282 vehicles were produced for the Canadian market, and 122 vehicles for the Mexican market.DTNA said that the remaining balance of parts were likely supplied to parts depots for service (service loops) for other purchasers, such as Freightliner dealers sourcing custom vehicle requests. RMD also requested and reviewed shipping and distribution materials from Bergstrom. These materials identified Park Smart units intended for MY 2014 Cascadia trucks (e.g., vehicles outside the DTNA recall population).RMD confirmed with DTNA that the MY 2014 trucks had the non-vented cap design used on them and so were properly excluded from the recall population.In addition to collecting information and documentation from the involved companies, ODI reviewed early warning reporting information. This search identified nine reports of thermal events. All events, however, occurred on MY 2014 Cascadia trucks that, for reasons explained above, were not part of the DTNA recall and the event linked to other causes. In view of the information available to it at this time, RMD is satisfied that the scope of the DTNA recall is adequate.Accordingly, this RQ is closed.
EA17001 · EA
VISIBILITY/WIPER Investigation
On April 3, 2017, the Office of Defects investigation (ODI) opened Engineering Analysis (EA17-001) as an upgrade to a Preliminary Analysis (PE16-005). The investigation focused on alleged windshield wiper failures on 2015-2016 MY Freightliner Cascadia trucks. ODI received Early Warning Reporting (EWR) field reports from the manufacturer describing wipers that intermittently failed to operate, causing a loss of visibility for the driver while driving in rain or snow. Several of the reports alleged multiple vehicles experiencing the failure, while multiple failures also happened on the same vehicle. Many of the field reports indicated the windshield wiper problem was resolved once the wiper motor was replaced.Following a detailed analysis of data collected by ODI it was determined that a low failure rate for a complete loss of wiper function existed on the subject vehicles. Given this low failure rate and the Technical Service Bulletins (TSBs) to address this issue released by DTNA, this investigation is closed.The closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists. The agency reserves the right to take further action if warranted by the circumstances.For a detailed summary of the investigation see attached closing resume document.The ODI reports cited above can be reviewed at: http://www-odi.nhtsa.dot.gov/owners/SearchNHTSAID using the following complaint identification number: 11141519
PE16005 · PE
VISIBILITY Investigation
On April 13, 2016, the Office of Defects investigation (ODI) opened this Preliminary Evaluation on 2015-2016 MY Freightliner Cascadia trucks, alleging windshield wiper motor failures. The investigation was opened based on EWR field reports describing windshield wipers that intermittently failed to operate, causing a loss of vision and increasing the risk of a crash. Several of the reports alleged multiple vehicles experiencing the failure, while multiple failures happen on the same vehicle. Many of the field reports indicated the windshield wiper problem was resolved once the wiper motor is replaced.Through communications with the manufacturer, ODI learned they had received 4 complaints, 12 field reports and 1,852 warranty reports involving the alleged defect on the subject vehicles. ODI was also made aware of a crash due to wiper failure during a rain storm. ODI interviewed both the owner and driver of the truck. The driver alleged he switched the wiper speed from intermediate to high and the wiper stopped working. During the loss of vision event, he lost control of his vehicle, hitting an embankment on the passenger side. The owner of the truck stated that after towing the vehicle back to their property, the function of the wipers was tested and they were found not to operate.The manufacturer informed ODI they had collected wiper motors from vehicles that allegedly had wipers fail and bench tested them. In each case they state the motor was found to operate normally. The manufacturer states they have not been able to duplicate the wiper failure problem as described in reports.This investigation has been upgraded to an Engineering Analysis (EA17-001) for ODI to gather additional information concerning wiper system performance. ODI will also study peer vehicles to understand how they perform relative to the subject vehicles.