On Dodge and Chrysler vehicle it's possible to retrieve codes without a scanner by simply cycling the key OFF-ON 3 times with last position being ON within 10 seconds. I've read and seen videos on this procedures so apparently it works.

Now last Sunday coming back from a road trip while driving on the highway my check engine suddenly came on followed by a single chime on my 2013 GC everything seem to be running normally. I decided to take the next exit off the highway and proceeded to nearest commercial parking lot shut the van off and do the OFF-ON key cycling routine to see what codes comes up NOTHING tried twice more same results even tried it with parking brake engaged same thing NOTHING. I pop the hood start the engine and went to check if I could see or hear anything again nothing out of the ordinary check the fluid levels all good so I proceeded back to the highway and drove home. I even tried the key cycling routine again in my driveway after it had been sitting for awhile same results. I decided to call a friend who happens to be an automobile technician who has a pro scanner I apologized for calling him a Sunday evening hoping to have it checked Monday evening he got me to go over right away. Pulled the van in his garage plugged in the scanner and it pulled up P0128 code low engine coolant temperature he then proceeded to change screen and was able to check the temperature sensor which check ok the culprit is the thermostat. We change out thermostat and cleared the code Monday evening I bought a Mopar thermostat rather than an aftermarket one along with a gallon of Mopar OAT 50/50.

I'm just curious why didn't the OFF-ON key cycling routine work in this case.

 

it only works for obd I vehicles pre 1996. anything obd II, 1996 and newer requires a scan tool to retrieve codes.

 

Any auto parts store will read the code for you. Or, buy yourself a scanner off amazon or at walmart. You can buy them for less than $20 these days.

 

That's false there's some videos showing some 2011 and 2014 Grand Caravan with check engine light on pulling codes using the key cycling method.

 

I just notice the odometer cluster is showing the outside temperature and I check another video on 2011 GC and it was also showing the outside temp in the cluster when they retrieved the codes. When I tried mine was it on odometer setting it seem in order to retrieve the codes you need to be on the outside temp setting.