2022 Toyota Redundant Sienna Electrical Problems

Pre-Collision System Malfunction, Hybrid System Malfunction, AWD System Malfunction suddenly when restarting the vehicle. Towed to Toyota of Downtown LA dealership. Toyota of Downtown LA Service tells me that the CPU on my relative new Sienna 2022 was fried from jump start when Sienna starting-battery was low.

When you apply the brakes to slow down your car, it accelerates instead of slowing down. This is a serious safety issue that needs immediate attention from a technician who can diagnose the brake and acceleration system.

Your van's hybrid battery repeatedly dies and won't hold a charge, causing the vehicle to fail to start and require multiple tows since May 2023. You're also experiencing multiple safety system malfunctions including ABS failure, seatbelt warnings, and Advanced Detection System errors, along with windshield wipers that randomly activate and won't stop. These issues have persisted across multiple repair attempts at different dealerships, suggesting a deeper electrical or battery management system problem that may require comprehensive diagnostic testing and potential hybrid battery replacement.

Your Sienna has suddenly accelerated or surged forward 30-40 times over 18 months, even while you're applying the brakes at low speeds (5-10 mph). This has happened while turning and driving straight, including in dangerous situations like crosswalks and traffic merges. The dealer says Toyota engineering indicated this may occur when the hybrid battery is fully charged and the regenerative braking system tries to charge it simultaneously, causing power to go to the motors despite brake application. The fix will likely require a software update to the hybrid system or inspection of the brake and regenerative braking integration.

Water has accumulated inside the wiring harness connectors for your rear tail lights, causing them to corrode and fail on both the driver and passenger sides. You may notice your rear tail lights not working or staying on. The dealer confirmed this is a known issue on 2022 Siennas. Fixing this requires replacing the corroded wiring harness connectors on both sides.

Your 2022 Sienna may experience a no-start condition while driving due to a malfunction in the DSM (a vehicle control module) that drains the battery and damages the battery cells. You'll need to have the battery replaced and the DSM software updated to fix the problem. The repair involves a software update and diagnostic work, but warranty coverage may be denied if your vehicle exceeds 36,000 miles, even though the software issue could happen at any time.

While braking to stop at a traffic light on a slight downslope, your brakes momentarily released for a second or two before re-engaging, similar to hitting ice or an oily patch. This happened once in a vehicle under 3 years old with 10,539 miles. The issue may involve the brake control system needing inspection or software diagnostics.

Your 2022 Toyota Sienna wouldn't start after a doctor's appointment. When you jump-started it following the owner's manual (which had no jump-start instructions in the engine compartment), the van started but only drove about 100 yards before stopping. The dealership found the battery had an internal defect and said the jump-start was done incorrectly, but a technical bulletin shows Toyota knew about inadequate jump-start instructions since April 2022—before you bought the vehicle. The bad jump-start reportedly burned out your Engine Control Unit, which isn't covered under warranty, costing $1,100 to replace, while the defective battery is covered. Fixing this will require replacing the Engine Control Unit and battery, and possibly updating jump-start procedures or warning labels.

Since getting a tire changed, your Sienna displays a recurring error message saying the tire pressure monitoring system is malfunctioning. This happens at least half the time, making it difficult to know your actual tire pressure. The dealership has serviced it twice over 30 days, replaced the tire pressure sensors, and test-driven it extensively, but the error continues to appear daily.

Your tire pressure monitoring system (TPMS) stops working when you drive at highway speeds, so you can't see your tire air pressure on the dashboard. The problem happens repeatedly, especially on interstates, and your dealer hasn't been able to fix it. This could be a safety issue if your tire pressure drops and you don't know about it.

Your van's hybrid battery cooling system is showing repeated error messages. This system was modified by Vantage Mobility International to add wheelchair accessibility features, and the dealer and Toyota have been unable to fix the problem after multiple attempts. You're concerned this may be a safety issue, but neither the dealer, Toyota, nor VMI have provided written confirmation or resolved it. The repair will likely require a diagnostic check of the hybrid cooling system and its electrical connections to identify and fix the underlying error.

Your integrated dashcam and forward collision avoidance system are causing continuous beeping. The dashcam was replaced once under warranty, but the beeping issue returned after 30,000 miles. A Toyota dealer should diagnose whether the replacement dashcam unit is faulty or if there's an underlying electrical issue causing the system to malfunction.