[Jgstockdale]

I have a 2015 optima eco hybrid with a distinct brake noise at the abs booster/ master cylinder I am also an ase certified gm tech of 30 years. I just took my kia in to the dealer asking the to diagnose the noise when I depress the brake pedal. I got the vehicle back he tech said he lubbed the pivot bushing and push rod and said noise was gone and that it is a normal noise due to wear, but nope it wasn't gone. So I did some looking and found a bulitien for the same noise on 2011-13 Optimas to chanr the brake line which the updated part has a dampner in the line. My question is , has anyone found any other bulitiens apply to 2015. Oh an my car ha 39,000.
Thanks.

 

[tonester]

You might want to look here:

2015 Kia Optima Hybrid TSBs

 

[Jgstockdale]

You might want to look here:

2015 Kia Optima Hybrid TSBs

Thank you I actually took it back to the dealer with the bulitiens and they said there was another updated bulitien that requires the whole IBAU (Integral brake assist unit) to be replaced and the the bleeding procedure wouldn't fix the vehicle.

 

[jbsfield]

Thank you I actually took it back to the dealer with the bulitiens and they said there was another updated bulitien that requires the whole IBAU (Integral brake assist unit) to be replaced and the the bleeding procedure wouldn't fix the vehicle.

Can you describe what the noise sounded like? I ask because my daughter brought her car over to my house the other day because it was making a noise when depressing the brake pedal. The car didn't have to be moving. It could be sitting in the driveway in park and if you depress the brake pedal it's almost like a creaking or groaning noise. It's hard to say if it's coming from inside the cabin or on the other side of the firewall. I tried lubing pivot points inside the car but it made no difference. Just wondering what yours sounded like.

 

[Ebratton2120]

Ok my wife’s 2018 Optima plug in…at odd times when pressing the brake pedal, there is a honking sound. It’s random, but does occur.
On the Kia service bulletin there is an audio sample.

So is this the problem folks are encountering?

She told the service about it and they didn’t do anything saying it’s not repeatable.

It would be nice to know the bulitin where it states the iBAU system needs to be replaced.
I didn’t see it, but having the bulletin and the audio sample is helpful.