The 'car wash test' is a simple reasoning benchmark that asks an AI model if it should walk or drive to a car wash 50 meters away. Most major AI models fail this test, with only 5 out of 53 models tested able to consistently answer correctly. The test highlights the limitations of current AI models in terms of contextual reasoning and reliability. The results also show that human performance on this task is higher than most AI models, with 71.5% of humans answering correctly.