I have a 2015 Honda Accord exl and the check charging system light came on. I checked for voltage at the battery and it was not charging. When I connect the positive lead wire of my meter to the alternator and negative lead to the negative terminal of the battery I get no voltage but when I put the negative lead on the positive of the battery I get 11.6 volts. The battery alone has 12.7 volts. I checked my other car and I got the same battery voltage when I connect the red lead to alternator and black lead to negative. Changed alternators and got the same results. How can two positives give me voltage.

 

When putting the positive lead on the alternator, you need to touch the large lead under the rubber boot to the alternator and not the small wire to the alternator and not the alternator housing. You should get battery voltage when the engine is not running and the charging voltage when the engine is running. It should be identical to what you measure across the battery posts.

 

I did that and I have no voltage. But when I leave the positive lead on the bolt under the rubber boot and put the black lead on the POSITIVE lead on the battery I’m getting voltage and even then it’s about 1 volt less than what the battery is reading

 

I'm guessing the charging light is still on and your battery isn't charging?

The only thing I can think of is the cable from the alternator to the battery + terminal is corroded/broken. Maybe the eyelet or the battery terminal isn't making good contact to the wire?

Was any work done recently on the car or an accident/damage? Have you ever changed out the battery cable terrminals?

 

Found the problem. The wire to the alternator goes around the back of the engine to the left side of the fuse block. The terminal must have gotten hot and melted the plastic preventing a connection. Alternator is working now. Thanks for the help