2011 Chevy HHR LT2, 128,000+ miles. Never changed the spark plugs since ownership, my bad!

An audible alert and ‘Service ESC’, ‘ESC off’ popped up on my DIC whilst driving home from the store yesterday.

I did my due diligence by using my ‘friend’ Google & YouTube after my FIXD OBD2 showed no codes were found.

After internet research I pumped up the tires to their recommended pressure, checked the brake fluid and 60 amp power steering fuse which were all good.

I disconnected the battery to reset the issue, but to no avail.

Today I went to my local AutoZone and specifically asked whether their scanner could interpret ESC problems. They weren’t sure, but elected to run a test on my behalf all the same. Suffice to say, I received a print out and the Check Engine and ABS test passed, but at the foot of the page under Test Results for ABS it showed code C0460-42, Steering Wheel Angle Sensor - Calibration Not Programmed.

That result is the exact opposite of their report previously stating that the ABS had passed.

As such, I am in a quandary as to what might be wrong.

Furthermore, I have watched YouTube videos where others have experienced the Service ESC alert and have replaced the purge valve solenoid with a positive result.

Personally speaking, the vehicle isn’t difficult to start, power steering is fine, idles well, but I have noticed the average mpg is fluctuating both widely & frequently and has dropped way down since this problem arose.

 

Get yourself a code reader that can read the ABS module.
Steering module.

 

When my ESC light came on, I checked to ensure the steering wheel was centred. Then with key on , I turned the steering wheel full left , then full right , then back to centre. I cycled the ignition off then on. This cleared the ESC light

 

ABS codes are not saved, they can only be read when the ABS light is lit.
Actually P0469-42 means "Steering Position Signal Initialization Not Accomplished". That means that the steering angle sensor is taking too long to report; which most likely indicates either a power supply or wire problem. Not whatever nonsense code reader came up with.

Do all of your tires match? Size. brand, inflation.
Has ANY work been done recently?
Check fuse #19 on the BCM (passenger side below radio).
Look for chafed wires under the dashboard around the steering column.

If a fuse is blown find and fix the problem that caused it.

 

All tire sizes and brands match, inflated to 35 psi.
No work has been done on the vehicle recently.
Fuse #19 is good.
No obvious signs of chafed wires.

 

What do you mean "audible alert"? A chime or a "grunch" like when the ABS activates.
. Does the car changing direction unexpectedly?
Any liquid spills around the gear shift?
Any liquid or something happening around the red circle?

 

By 'audible alert' I mean chime, just like you hear if a seat belt isn't worn.
No noticeable difference with the power steering which is working and the vehicle doesn't change direction suddenly.
There haven't been any liquid spills.

 

Must be gremlins or a bad steering angle sensor or EBCM. It doesn't really have anything to do with the power steering like it sounds. It is a sensor that works with the ESC along with the yaw/lateral acceleration sensor and the wheel speed sensors; to tell the computers if the car is going in the direction the driver intends. If the car is turning and the steering wheel is straight the ESC activates and attempts to correct by using the ABS system. The computer involved is the ElectronicBrakeControlModule.

 

Any alignment shop should be able to relearn the SAS it’s probably not bad just out of parameters.

 

I keep researching my issue on the internet and I can dispel YouTuber's who post videos of turning the steering wheel lock to lock from center and back to clear the ESC code. Myth busted I'm afraid when it comes to HHR's.
Further, I checked the purge valve, also posted as a possible cause. It pulled a vacuum after warming up so I assume that is good.
Interestingly enough now, I have just noticed that only the LR TPMS is showing the tire pressure and the other 3 tires are blank whereas they were good prior to today I think.
Could this TPMS problem have any bearing on the ESC?