Ecu Errors P0556 And P0557. Engine Light Is On!

[alligator]

Hi everyone,

I'm new in this forum and I hope that you can give me some info about the following errors. I have them for a very long time and the garrage which I use is not giving me more details. They think that this is possibly because of ABS but not sure and prefer to change the whole ABS?!?

The errors are:

P0556 = Brake Booster Pressure Sensor Circuit Range/Performance

P0557 = Brake Booster Pressure Sensor Circuit Low Input

There is nothing which makes my driving different and the only problem is that the Engine Check light is ON and cannot be turned off. The brakes are stopping quite well and ABS and TRC are also without issues. After erasing the error from the ECU it appears again after 1-2 seconds. It also happens in stopped car without started ignition. Is there someone who faced the same errors and do you know what could raise them?

My car is Avensis 2004 T25 Luxury edition.

Thanks for your help in advance.

[Whitewagon]

An abs fault doesn't always mean you have a completely new unit but a lot of repairers prefer to take this course either because they don't have the expertise to carry out a repair or that it's the easiest option.

Take a look at this company http://www.sinspeed.co.uk/. I haven't used them myself but they do come recommend in other forums.

[alligator]

Unfortunately, I'm not in UK and this solution will probably not apply for me. I only tried to find what could raise this problem and what mean those errors.

[alligator]

For everyone who can face this issue in the future.

I took over my car to Toyota dealer and they found the problem. A sensor placed on the brake pedal generates these errors. They resolved the issue and now everything is fine.