2019 Freightliner Cascadia

On May 26, 2023, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE23010) to assess reports of false positive activation of the Automatic Emergency Braking (AEB) system in model year (MY) 2017-2022 Daimler Trucks North America (DTNA) vehicles. The reports alleged that activation of the AEB system occurred while driving with no apparent obstruction in the vehicle's forward path, resulting in sudden vehicle deceleration. DTNA indicated that it received of a total of 315 reports that may relate to the alleged defect in MY 2017-2022 DTNA vehicles. DTNA stated that the vast majority of false positive activation of the subject systems occur in very limited durations and result in a five mile per hour deceleration. ODI considered four AEB systems offered by DTNA: Detroit Assurance 2.0, Detroit Assurance 4.0, Detroit Assurance 5.0, and Wabco OnGuard.  ODI’s analysis shows that of the Detroit Assurance versions, all are failing at similar rates. The OnGuard AEB systems equipped on the same model and model year vehicles have experienced a significantly lower claim rate. To date, ODI has received a total of 32 consumer complaints of inadvertent activation of AEB in MY 2017-2022 DTNA vehicles. In total, ODI reviewed 347 unique (i.e., non-duplicative Vehicle Identification Numbers) reports that may relate to the alleged defect, which include 24 reports involving a crash, 13 reports involving an alleged injury and one report with a fatality. PE23010 has been upgraded to an Engineering Analysis to further assess the scope, frequency, and potential safety related consequences of the inadvertent AEB activations in MY 2017-2022 DTNA vehicles. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

On May 26, 2023, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE23010) to assess reports of false positive activation of the Automatic Emergency Braking (AEB) system in model year (MY) 2017-2022 Daimler Trucks North America (DTNA) vehicles. The reports alleged that activation of the AEB system occurred while driving with no apparent obstruction in the vehicle's forward path, resulting in unexpected and sudden vehicle deceleration. ODI sent an information request letter to DTNA on June 15, 2023.In its September 1, 2023, response, DTNA indicated that it received of a total of 315 reports that may relate to the alleged defect in MY 2017-2022 DTNA vehicles. DTNA stated that the vast majority of false positive activation of the subject systems occur for very limited durations and result in a five mile per hour deceleration. ODI considered four AEB systems offered by DTNA: Detroit Assurance 2.0, Detroit Assurance 4.0, Detroit Assurance 5.0, and Wabco OnGuard. ODI’s analysis shows that of the Detroit Assurance versions, all fail at similar rates. The Wabco OnGuard AEB systems equipped on the same model and model year vehicles have experienced a significantly lower claim rate. To date, ODI has received a total of 32 consumer complaints of inadvertent activation of AEB in MY 2017-2022 DTNA vehicles. In total, ODI reviewed 347 unique (i.e., non-duplicative Vehicle Identification Number) reports that may relate to the alleged defect, which include 24 involving a crash, 13 reports involving an alleged injury and one report with a fatality. PE23010 has been upgraded to an Engineering Analysis (EA25006) to further assess the scope, frequency, and nature of the inadvertent AEB activations in MY 2017-2022 Freightliner Cascadia and Western Star 5700 vehicles.In particular, this EA will assess the safety consequences likely to arise in the scenarios during which the AEB inadvertently and unexpectedly activates, such as the speeds and conditions during which the activation occurs. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

The Office of Defects Investigation (ODI) opened this Preliminary Evaluation to investigate reports of engine electrical wiring harness chafe on the subject vehicles.ODI analysis found thousands of unique harness part numbers, spanning the two generations of vehicle chassis assembled at multiple vehicle assembly plants in two different countries, with multiple sub-models, incorporating over thirty powertrain choices.Each wiring harness could contain several dozen individual wires for power, ground and communication purposes depending on the multitude of equipment options available for custom vehicle configuration. ODI identified three primary areas where a wiring harness bundle may chafe: the air compressor support bracket, the transmission case, or the coolant surge tank. In each case, the root cause was some combination of inadequate design clearance, installation variability and relative motion between the wiring harness and the point of contact, such as from vibration. The chafing could result in a range of consequences from none to various diagnostic fault codes, telltale illumination, driver warning center messages, erratic electrical component operation, difficult or no engine start condition, engine de-rate (power reduction), engine shut down, inoperative transmission gear selection, or an unexpected shift to neutral.These potential consequences vary depending on the specific damaged wire in the harness and the exact failure mode, such as intermittent short circuit to ground or open circuit. Generally, the chafing resulted in a progressive series of driver warnings with high levels of detectability over the course of several days and ignition cycles. Drivers usually heed warnings before an engine shutdown condition occurs and the driver may override an engine shutdown countdown timer using the override switch. If the driver allows the shutdown event to occur, the engine can almost always be immediately restarted. Incident rates for an engine shutdown with no warning or a transmission shift to neutral while driving are both very low. ODI received one complaint (NHTSA ID Number 11366557) from a fleet mechanic, who reported in a subsequent interview that he repaired at least six subject vehicles that experienced the alleged defect condition. However, there have been no new Vehicle Owner Questionnaire complaints received by ODI since opening this investigation, and there are no known crashes, fires or thermal events, or injuries or deaths related to the alleged defect. Accordingly, no safety-related defect trend has been identified. Based on available information, 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 reserves the right to take additional action if warranted by future circumstances. To review the ODI report cited in the Closing Resume ODI Report Identification Numbers document, go to NHTSA.gov.

In its process for evaluating Early Warning Reporting data, the Office of Defects Investigation (ODI) found twenty-four (24) field reports involving headlight fires on Freightliner Cascadia trucks, model years 2017 and newer produced by the vehicle manufacturer, Daimler Trucks North America (DTNA). ODI contacted DTNA and learned that it was aware of halogen bulb-related thermal events. DTNA stated a belief that the issue was due to incorrect bulb replacement during maintenance. However, some vehicles experienced fires within the original equipment halogen bulb's expected life range.In July 2019, DTNA released a service bulletin and a training video covering proper headlight bulb replacement. There have been 17 fires, with 3 total vehicle losses, since DTNA released this extra training information.On February 25, 2021, ODI opened a Preliminary Evaluation (PE21-006) and sent an Information Request (IR) letter to DTNA.After the PE opening, DTNA reevaluated the data and found additional thermal events at low mileages and decided to file a recall. On May 14, 2021, DTNA submitted recall 21V-357 for 72,508 vehicles covering 2017-2022 models (exceeding the population and model years of this investigation). The planned owner and dealer notification date is July 12, 2021.For the remedy, DTNA will open up the 2-inch access into a 4-inch access hole into the inner fender to provide better access for the maintenance replacement of the bulb, and add a label that provides a visible warning to aid in the correct installation during the change. Additionally, a new foam grommet will replace the flammable rubber boots for both the high and low beam bulbs, improving access to the interface point where the bulbs install into the socket of the reflector. ODI believes that the scope of DTNA recall 21V-357 is sufficient, and accordingly, PE21-006 is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist on other models or MY vehicles outside of the recall scope. The agency reserves the right to take further action if warranted by the circumstances.

I am writing to bring to your attention a potentially dangerous situation caused by what I believe to be a manufacturer design flaw with the SS 1034797 M2, 108SD, 114SD Coolant Level Sensor P/N 06-93316-002. On [XXX], one of our trucks (VIN: [XXX]) experienced a low coolant warning and an automatic engine shutdown while traveling on the interstate in a construction zone. As you can imagine, the sudden stoppage of a tractor-trailer in the traffic lanes of a freeway presents an extremely hazardous situation, not only for our driver but for all motorists in the vicinity. For us as a motor carrier, this is compounded by the likelihood of legal liability resulting from any collision involving a stationary truck in such conditions. The root cause of this incident appears to be the failure of the magnet within the surge tank to maintain its buoyancy. When the magnet sinks to the bottom of the tank, it signals the engine control module (ECM) that the coolant level is critically low, triggering an engine shutdown. While I understand the intent is to protect the engine from potential damage, this design flaw creates an unacceptably dangerous scenario—especially since, in many cases, the engine is not actually at risk of damage. In this instance, I instructed the driver to unplug and after a 15-minute period, he restarted the truck and drove to a nearby truck stop. Remarkably, the truck remains operational without the sensor repair, further underscoring the superficial nature of this issue. Unfortunately, this is not an isolated incident. We have encountered similar sensor failures across our fleet, but this particular event was the most severe. While I am not an engineer, it seems logical that the coolant level sensor should be paired with a high-temperature reading before an engine shutdown is initiated. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11634519

Incident

Jan 6, 2025

While approaching an overpass the collision mitigation system activated my brakes nearly causing the vehicle behind me to rear end my trailer, hit my brakes so hard i was thrown forward.

NHTSA ID

11617194

Incident

Sep 27, 2024

My 2019 Freightliner Cascadia forward collision brakes activates automatically while on the road without any other vehicle nearby, airbrake malfunction (not released appropriately and fully released) and extremely fuel consumption.

NHTSA ID

11610330

Incident

Jul 12, 2024

Truck will apply brakes when no objects or vehicles are around. It is very scary and unexpected when the system does this.

NHTSA ID

11591674

Incident

Apr 16, 2024

The contact owns a 2019 Freightliner Cascadia. The contact stated that while driving at various speeds, the Forward Collision Avoidance feature engaged inadvertently. Recently, the contact stated that while driving at 45 MPH, the brake assist system engaged after a plastic bag flew by the vehicle. The Forward Collision Avoidance alarm sounded during the failure. The contact called the local dealer and was informed that the feature could not be deactivated. The manufacturer was also notified of the failure, but no assistance was provided. The failure mileage was approximately 254,180.

NHTSA ID

11580899

Incident

Apr 3, 2024

Mileage

254,180 mi

The contact owns a 2019 Freightliner Cascadia. The contact stated that while driving approximately 60–70 MPH, the brake assist system engaged without an object nearby. While depressing the brake pedal, the system released and reset. The Forward Collision Avoidance alarm sounded. The contact called the local dealer and was referred to the manufacturer. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 200,674.

NHTSA ID

11534282

Incident

Jul 25, 2022

Mileage

200,674 mi

My truck just came to a screeching halt on the interstate with no obstacles in front of it. It nearly caused a major accident. I could not override it. I was approaching an overpass approximately 100 yards away. Collision warning lights went on. Horn started beeping and brakes engaged immediately.

NHTSA ID

11530515

Incident

Jul 5, 2023

This complaint comes from a private truck fleet operating over 700 trucks experiencing excessive amounts of false positive emergency braking and/or haptic following distance warnings (brake stab) on 2018-2020 Freightliner Classis Cascadia tractors. The system experiencing the highest incidents are equipped with the Wabco OnGuard Collision Mitigation System. Some of these false positives have resulted in neck and shoulder injuries. False positives occur while approaching bridge overpasses and other road objects such as steel plates or overhead signs. Wabco has been contacted and state the system is discontinued and outdated so no support or fixes is offered other than a single software upgrade. All units have received the software update but still experience false positives. These unexpected false positive occurrences have resulted in injuries, potential loss of control, and accident risks to other motorists. Although false positives have occurred and continue to occur since first receiving trucks with this technology in 2018, the first injury occurred on 3/3/2022. The system should be recalled to provide a solution to the excessive false positives.

NHTSA ID

11530075

Incident

Mar 3, 2022

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