What does fault code u111300 mean?
3 Answers
Fault code u111300 indicates that the ABS operation signal is out of tolerance. The Anti-lock Braking System, commonly referred to as ABS, is a safety system that prevents the wheels from locking up during braking. Here is some relevant information about ABS: 1. The function of ABS is to automatically control the braking force during vehicle braking, preventing the wheels from locking up and maintaining a state of rolling and sliding (with a slip ratio of around 20%), ensuring maximum traction between the wheels and the road surface. 2. When the wheels are about to reach the next lock-up point, the brake fluid pressure causes the system to repeatedly engage and disengage, operating 60 to 120 times per second. This action is similar to continuously applying and releasing the brakes, akin to mechanical 'pumping' of the brakes.
I just encountered this trouble code U111300 at the repair shop, which is usually caused by communication issues. Last time my Passat showed this code, the mechanic said it was because the ABS control unit couldn't 'talk' to other modules. It could be due to loose wiring connectors or a control unit malfunction. What's more troublesome is that outdated software versions can also cause this, requiring a system upgrade at the dealership. Remember to check if there's any damage to the wiring between the gateway module and the engine computer, especially since rainy days make these issues more likely. It's recommended to use a professional diagnostic tool to read the freeze frame data, checking parameters like vehicle speed and coolant temperature when the fault occurred for targeted troubleshooting. Don't end up like me last time, spending hours tinkering only to find out it was just an oxidized connector causing poor contact.
With over a decade of car repair experience, I've seen this fault many times. U111300 essentially means dropped calls between internal vehicle communications. Control modules send messages to each other - for instance, when the engine tries to send RPM data to the ABS, but the ABS fails to receive it, triggering this code. Focus on three key areas: check for loose power connections, whether the module itself is faulty, and communication lines like the CAN bus. Particularly in German cars, the gateway module on the left side of the trunk is prone to moisture intrusion. Last time I fixed this issue on a Tiguan for a customer, replacing the wiring harness with a shielded one solved it. Simply cleaning the connectors can be a temporary fix, but for a proper solution, you need to locate the gateway connector in the engine compartment.
