Help with Fault codes 2009 VE SV6

[ssnowballs]

ABS & Check engine light on
ESP OFF

Scanned faulty codes on dash.

C0045-5A, C0050-5A - Low brake pressure left and right.

C027B - Vacuum pump.

Previous owner mentioned both rear abs sensors needed replacing. Replaced and all lights turned off, few days later I had driven a 5 hour round trip went over a small bump in the road and the ABS and check engine light popped back on. I had changed these after getting the car scanned.

Anyone able to point me in the right direction? Or would I be better off taking it in to a mechanic?

 

[krusing]

You mentioned going over a bump in road, and both DTC’s activated,
Common denominator possibly the loom from the fuel tank area.
That Pinpoints to a loose connector,
Check the connectors haven’t dislodged,
Or have moisture in them,
Follow the LH & RH loom to another connector near the fuel tank octane sensor connector, located just in front of the RH Rear wheel, (under the car adjacent the RH K-frame bolt) check that it’s not damaged, or dislodged,
I did read in another thread, that some early VE models did have a issue with the ABS loom to the rear wheels sensors,

Before checking the connectors and loom,
Disconnect the battery, and turn the ignition on to drain any residual power,
Turn it off and precede with the checks,
Remove every connector one by one and spray the plug and sensor with a contact cleaner,
If the fault has been rectified, and when you re-connect the battery, it should of reset the fault/s
If not, try and rest it with a scanner,
And do a few road tests,
If it is still faulting check the loom with a multimeter for continuity from end to end.

You can do the above checks and testing yourself , which will save you some $’s, and possibly an easy fix,

 

[BlackVXGTS]

Refer to the attached from the Holden VE Service Manual (your fault codes have nothing to do with brake pressure):