Faulty SBC investigation

[wysocki.michal@protonmail]

Hi Fellas
I decided to do some investigation myself before I send my SBC to JohnySBC for repairs. I have connected my Star diagnostic tool and read the errors from the SBC unit. This is the list of the errors I got:

C235A - Check component A7/3 (SBC hydraulic unit)
C25D4 - Hydraulics fault: No or insufficient pressure supply
C26DE - Hydraulics fault: Malfunction in pressure supply
C26BB - Hydraulics fault: Malfunction in pressure supply

I decided to replace the break fluid and bleed the system using Star. All errors apart from C235A went away which suggested there was air in the system. I did some reading and found that this error could be caused by worn brushes. I took the unit out, removed the motor cover and the brushes were indeed worn out. I have order new long life brushes and replaced the old ones. I have put the unit back in and bled the system using star again. The car breaks as it should but the error is still there. With the break pedal pressed I have read the values of the SBC related sensors. This is what I got:



For some reason rear left and right sensors both read 0. I suspect this could be an issue. Is the sensor built into the unit itself? Any help would be much appreciated.

Best Regards,
Mike

 

[wysocki.michal@protonmail]

I have asked the same question on the MHH Auto forum. One of the users suggested to follow this procedure to get rid of the fault code:

. I can confirm it worked and the C235A is no longer displayed.
The total cost of fixing my SBC pump: 25 pounds.

Best Regards,
Mike

 

[ecoman]

Thanks for posting this Mike
I've a similar problem and cleared it using Neistovij write-up on MHH Auto. It returned almost immediately as C235c. I'll be changing the brushes in next couple of days, but i was concerned that A7/3b5 and A7/3b6 could be an internal fault with the unit, possibly valves or solenoid.



"For some reason rear left and right sensors both read 0." - was this cured after the brushes were changed and reset using Star?


cheers