Got a 2007 hhr. Both thermostat gages stopped working and ac is blowing hot air. Engine light is on. Car is not running hot and runs fine. Not having a ac in South Alabama is killing me.

 

The thermostat is stuck open causing code P0128, this will stop the AC from working.

https://www.chevyhhr.net/forums/how-...l-p0128-24493/

https://www.chevyhhr.net/forums/how-...-system-60614/

Install new AC Delco 131-158 180 degree thermostat and fresh Dexcool 50/50 mix. Make sure you burp the coolant

 

P0102 usually comes from forgetting to plug the MAF back in after an air filter change.

 

https://www.obd-codes.com/p0102

Agreed, check the MAF is firmly plugged in, then double check the codes.

 

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Oldblue. You really should turn off that weird spellchecker you use...

 

I'm getting codes P0101, P0113, P0128. Mass or Volume air flow circuit low input

 

Well gee, that's not what you said in the beginning.
Your MAF is either not plugged in or not plugged in correctly.
Your t-stat needs to be replaced with the afore mentioned part.

 

How does it run? Is the AC fixed?

 

It runs just fine.

 

One more time:
P0128 disables the AC and the temp readout. It means that the engine temp has not risen fast enough and probably not high enough . Usually this is caused by a stuck open t-stat or a missing t-stat sometimes a faulty engine temp sensor. The engine is supposed to run at OVER 180F; the t-stat controls the MINIMUM temperature, the radiator/fan control the MAXIMUM temperature.
The reason it disables the readouts and AC is to get the drivers attention, since most people think petty icons on the dashboard are normal.

P0101, P0113, P0102 all refer to the MAF sensor. The Intake Air Temperature sensor is integral to the MAF. These are all for the MAF either faulty or bad wiring.