hi everyone,
I have a 2018 manual V6 coupe, and about 1 month ago I had the check engine light go on without any other changes, x for 1 difficulty starting, and then later tha it was gone. Today it started again and also had the snowflake indicator and an inaccurate temp reading. It was also running a bit rough with a higher idle speed. 2 hours later when I restarted the car, no check engine light and no other indicators and temp is accurate.
Hoping I could get some advice on this. I love this car, but have only some foundational knowledge so any education is appreciated.
Thanks,
Nick

 

Use a code reader to pull the codes. List them up here.

 

Put a battery charger or maintainer on the battery and charge it to 100% full. If issues persist after that have the battery tested, or test it yourself.

 

@ftypemaniac, with the ignition in the OFF position for at least 30 minutes, use a voltmeter to read the available voltage across the battery terminals. If the voltmeter indicates less than 12.6 volts, charge the battery for three to five hours at 2 to 5 amps and retest. If the voltmeter still indicates less than 12.6 volts, the battery is suspect and should be replaced.

Many random instrument cluster warnings and random DTCs are the result of a failing or weak battery.