Toyota GR Yaris AWD System Can Overheat, This Is What Happens When It Does

If overheating happens, the system will disconnect the rear axle, which will lead to the car working in two-wheel drive mode, which means it will just send power to the front wheels. According to YouTuber Xthilox, a Toyota GR Yaris owner, the disconnect works in two steps.

Owners of the GR Yaris who complained about overheating issues with their all-wheel-drive systems on the dedicated forum believe that the issue appears when the clutch packs in the center differential overheats, which is when the car's systems tell its computers to disconnect the rear axle. The GR Yaris comes with three transmission temperature sensors, which means it is easy to determine which of the components gets too hot for its good.

When the situation occurs, the driver will be informed through a message on the screen between the gauges. It is worth noting that Toyota recommends that GR Yaris users change their oil at half the specified distance or after track use if the vehicles are subjected to continuous high speed or track use. Along with the engine oil and filter, Toyota recommends a fluid change for the transmission, transfer case and differential fluids.

Toyota is testing another GR Yaris-based model at the Nürburgring for a few weeks now, and the Japanese automaker may be preparing an improved version of the model. Likely, the engineers have already seen the overheating issues during their tests, and maybe the development team has figured out a solution.

Owners of GR Yaris models are pondering whether to get a transmission cooler or a larger differential cover. The latter is a costly upgrade, while the former may delay the issue if not stopping it entirely. Both solutions would void the warranty of the car unless the Japanese automaker decides to issue a technical service bulletin that would allow dealers to install such items in customer's cars to prevent further problems.

Invariably, the GR Yaris is not the first, nor the last car to suffer from overheating issues at the track. That is why many time attack events go on for just a few laps when street-going cars are concerned, and a cooldown lap or two is included in most of these events for this purpose.

In the video below, you can see YouTuber Xthilox drive his GR Yaris with and without all-wheel drive as the car disconnects its system upon overheating. He manages to keep the car under control even after the system disconnects, which means that the engineers did a good job in the first place and managed to create a smooth transition between all-wheel drive and front-wheel drive without unsettling the car.