Got the "check charging system" message about ten days ago when I was on a road trip. Pulled over and bought an alternator and put it in. It was some cruddy brand that I had never heard of but it was the only one they had in stock that fit. FF to 10 minutes ago and the same message popped up. I'm still driving(stuck in traffic) and it hasn't popped up again. Could it have been a fluke? Any contacts I need to check/clean? Any help is appreciated.

 

You need to get the DTC code that tripped the "Check Charging System". It could be the Asense line, power feed line, battery connection, lose regulator connector or actually a faulty alternator. At very minimum, check the charging voltage. I would only replace an alternator if it wasn't putting out voltage/current to keep the battery charge on a highway drive cycle.

 

Thanks for the advice, Stormsearch. My truck's been sitting in my parents garage for the past few days. I'll take the multimeter out today and get some readings from the charging system. The new alternator was whining since I first turned the truck over with it in; as if the bearing was bad. Since I didn't replace the belt I assumed it was metal shavings in the belt going over the new pulley. I'll post back with my findings this afternoon

 

As a helpful guide, here's what you should be getting with a optimal battery and alternator:

Truck turned on and charging 14.1-14.4v.

Truck turned off with NO load 12.5-12.7v.

To do a simple load test, turn on headlights with high beams on and measure the voltage drop. If it drops below 11v, then I'd replace the battery.

Sounds like you might have a bad cell in your battery.

 

So after having 2 rebuilt alternators from one of the big box stores fail on me (after the original failed after 178k) I finally have a brand new alternator made in the USA in there. I knew something was up with the second rebuilt alternator when I couldn't spin it one complete rotation free-handedly. Battery read 12.5 when I checked it before installing my newest alternator. The alternator is reading 14.24 when I last checked. It has only been in for 2 days so we will see if the check charging system DTC shows up again. Hopefully this will solve my issues. Thanks for the help everyone. I guess you get what you pay for... even though my american made alternator was cheaper than the rebuilt products.