My 2004 has about 160k on it now. Alternator has never been replaced. Recently I have been getting the alert "check charging system"

So I check the battery terminals with engine running and all lights and AC running. I was getting less than 12V. But while waiting for a new alternator to arrive I am now getting 13v and no warning.

So what is the proper troubleshooting for the charging system? I always used the voltmeter to check voltage at battery terminals. But my problem seems to be intermittent.

 

There an't much to trouble shoot, you should be getting 14.5 V and steady, a new alternator was correct call.

 

alternators last 150 - 175 K miles "average" so it is time. Yours has worn brushes so it is intermittent on problem. Clean battery terminals and all ground straps that look cruddy when you install the new alternator.

 

Yep. It is solved. But I had to run out and buy one locally since the online purchase took too long. Now I have a spare.

 

How old is the battery? It's not bad practice to pair a new alternator with a fresh battery.

 

You mean to tell me that damn thing has brushes in it like the generator on my ole 54 model?