ABS faults C1256, C1252

[fredjaj]

Hi,

ABS about to die

1. The problem is intermittent, I feel the abs motor running for a long time. upnormal.

It stops for a short time and starts again. It has a short operating cycle. When you press the brake pedal, the abs motor never stops operating.

2. When the brake pedal is pressed for a long time, an alarm light and beep warning activated.

Code C1256 and C1252

So I want to rebuild the ABS unit myself. I have the diagnostic tools and good mechanical experience, as I usually repair my car myself. But before I start, I want advice from you, what most frequently cause this code 1265., and what parts to start with?

 

[felix2566]

Have you checked you dont have any brake fluid leaks or wiring issues first?

I dont know the specifics of your vehicle but is there not a seperate brake booster pump, or is it all built into the ABS unit?

 

[fredjaj]

Have you checked you dont have any brake fluid leaks or wiring issues first?

I dont know the specifics of your vehicle but is there not a seperate brake booster pump, or is it all built into the ABS unit?

Hi, thanks for your reply
Its 2010 Toyota LC200 with one unit ABS Brake Booster, Accumulator, Pump etc see the picture.

No visible leakage.
Wiring issues! Not sure but I'll check it out.

 

[Juddian]

The brake master cyl/abs/booster/accumulator unit pictured looks very similar as those fitted to 120/100/150.
Often if there's an issue its the booster motor itself going faulty, not saying that's the issue here but the error messages in the pic point in that direction.

One or two people on the various forums in the UK have had success sending their booster/accumulator motor to a specialist rewind workshop in London,
these people Electric Motor Repairs, armatures, London, Rewinds, Robson and Francis - [Leaving Land Cruiser Club]

Probably not much use to you because distance but they might offer some advice if you contact them, but hopefully unless you can fit the issue yourself there is somewhere similarly skilled in your country.

As far as i'm aware Toyota don't supply individual parts for the combined brake unit so repair/refurb is the only way forward other than a good used unit, but if anyone knows different i am happy to be corrected.

 

[felix2566]

What kind of diagnostics tool do you have. If possible I would go into the ABS control area and you should be able to activate all the individual components of the system. That will really help isolate what the issue is.
Should be able to pulse the individual solenoids and run the motor.
Plus have a look at the data for all sensors in the system. Are the readings they give out plausible, it might be a sensor that is inhibiting the motor from running properly.

 

[fredjaj]

The brake master cyl/abs/booster/accumulator unit pictured looks very similar as those fitted to 120/100/150.
Often if there's an issue its the booster motor itself going faulty, not saying that's the issue here but the .

Thanks i really appreciate your help.

That's true they are actually similar but different in details but the same hydraulic operating method, Unfortunately, in my case, it doesn't seem to be an motor problem yet، but I will check again.

I will take your advice. Thank you very much.

 

[fredjaj]

What kind of diagnostics tool do you have. If possible I would go into the ABS control area and you should be able to activate all the individual components of the system. That will really help isolate what the issue is.
Should be able to pulse the individual solenoids and run the motor.
Plus have a look at the data for all sensors in the system. Are the readings they give out plausible, it might be a sensor that is inhibiting the motor from running properly.

Hi, Thank you for your help i really appreciate it

I use Techstream diagnostic I will check all the available options for the ABS system.

but i think Techstream has limited options, I don't think can do active test with ABS components، example active the motor or active valve, but i'll save/log all Live data from abs unit.

If there is any other option that helps in identifying the problem, please let me know.

Thanks again for your help

 

[felix2566]

If you can find a friendly garage who can plug diagnostics in, or even pay for them to do some diagnostics, it might save you time and money identifying what is actually wrong before pulling the trigger on parts.

From personal experience the fault codes are not always indicating the actual part at fault so you need to do a bit more digging to be certain of what's not working.