Table 1 shows two common lane departure related problems of the 2021 Toyota Sienna.
| Problem Category | Number of Problems |
|---|---|
| Blind Spot Detection problems | |
| Assist problems |
1. The vehicle displayed the rear cross traffic alert (rcta) warning light along with the blind spot monitoring (bsm) warning light on the dash board. The vehicle was brought to Toyota of ann arbor for an inspection. After inspecting the vehicle, Toyota of ann arbor reported that road debris (snow, dirt, mud, etc. ) was trapped between the bumper and the sensor resulting in the sensor to malfunction. The vehicle has been taken through a car wash with an underbody wash option, but due to the position of the sensor, the sensor is not able to be cleaned from a car wash. The sensor can only be cleaned by removing the bumper. But when the bumper is removed, the sensors have to be re-calibrated and the re-calibration of the sensors can only be completed by trained professionals. 2. Due to the malfunctioning sensor, the driver's safety is put at risk by not being alerted of obstructions (both objects or persons) behind the vehicle, nor oncoming cross traffic, nor detecting vehicles in blind spots. This could cause collisions or worse, fatality, due to the malfunction sensor not alerting the driver. 3. This vehicle has been able to reproduced the problem multiple times and as mentioned above, the vehicle was inspected and confirmed by the Toyota of ann arbor dealership. The dealership (Toyota of ann arbor) mentioned that there are multiple reports of this issue on other vehicles of the same make and model. 4. The vehicle or component has not been inspected by the manufacturer, police, insurance representative, or others. 5. No prior symptoms were seen or displayed prior to the failure.
Van has just over 5k miles. Multiple warnings occurred while at speed on a highway. Primary warning was 'low brake power' and braking became extremely touchy as it seemed to utilize the emergency brake as a backup. This extreme braking is hazardous and could result in an accident caused by braking too quickly - with a possible rear-end collision by traffic to the rear. Additional warnings/malfunctions were listed as well, due to the low brake power: lta malfunction (lane keep assist), automatic emergency brake malfunction, parking brake malfunction, check engine. There were no symptoms of poor braking prior to the incident. Dealer filed a tas report with Toyota to address the problem, and was subsequently inspected by the Toyota field representative. Initially could not duplicate/identify the issue and the van was returned. Within one week the incident reoccurred, again on the highway. Van is currently with the dealer and the brake booster and brake master cylinder will be replaced. Expect the dealer will retain the parts.