2009 3.8 Genny ABS & ESC lights on

[bobmarley421]

While taking a left turn today the rear end slipped out a little and both the ABS & ESC lights came on and stayed illuminated. Stopped by Advanced auto and had them hook up the code reader and it showed no codes. Any ideas?

 

[OneFunGenesis]

Sub'd. This is weird.

 

[homeofstone]

Could be a sensor problem.

 

[OneFunGenesis]

I was actually thinking a Hub/Bearing problem. I know that on some cars, the ABS is tied into the ESC system. And when the hub messes up, the ABS sensor sends a fault.

Does the car drive/sound any differently?

 

[bobmarley421]

Well they both stopped coming on yesterday when I started it up and havent been back on since knock.. knock..

 

[OneFunGenesis]

what the...?

 

[mikec]

The ESC and ABS computer is the same unit - the "HECU" as Hyundai's brake system service manual calls it. (Hydraulic and Electronic Control Unit) The functions are combined in this box, as well as the EBD (Electronic Brake force Distribution) function. A "diagnostic" flowchart in the manual includes a branch with "diagnostic code set" yes/no... and "no" leads to "intermittent fault" and stops there.

Later in the manuals there is a discussion of some causes for various warning light combinations. Most that cause ABS and ESC and don't light up EBD are due to a single wheel speed sensor going bad for a moment most likely due to wiring harness problems. Not-fully-seated connectors seems to be one of the more frequent assembly line "oops" on these cars. Mine had one on an engine camshaft position sensor - it wasn't fully snapped down and generated a check engine light weeks after I bought the car. Similar loose connector issues have caused door lock and window switch problems reported in these forums. The factory manuals suggest inspecting the wiring & connectors near each wheel. Such failures are supposed to set codes C#### but not all code readers can read/access the extended manufacturer specific code set.

mike c.