Hey guys,

I have a 2011 GS350 with 264k miles. This past Friday I noticed a notification ding sound but no message or lights on the dash. It did it again a few minutes later and then a third time. After that the battery light came on with a message to check charging system. It would go off after a few minutes but come back on again. It came back on again for about 10 minutes and then went off for the rest of that day.

I drove to and picked up a rental just in case since my car is used for work travel and need transportation. I made it to Hertz with no issues or warning lights. I then drove my GS back home with no warning lights on or check charging system on. It drove fine and everything worked like normal.

Fast forward to today and I went to go look it over. Belt looks good. No whining or grinding sounds. I disconnected the battery for over an hour. When I reconnected it it drove fine for a few minutes. The the check power steering system message came on but the steering was fine. All accessories worked. Also the AFS light is now flashing.

I drove it to O’Reilly to check battery and alternator. Both battery and alternator tested good. Volt reading for alternator was showing 13.7 and dropped to 13.5-13.6 when a/c, radio and interior lights on.

After it was tested the check power steering message came back on but only when in park. As soon as I put it in reverse or drive the message goes away but the AFS light is still flashing.

Car drives normal. Everything works like it should with no noticeable issues.

Current state:

No battery light on or check charging message.

AFS flashing even thought I didn’t jack the car up for anything, just sitting in driveway.

Chekc power steering message and red wheel light on, but only in park. Goes away immediately after putting it onto R or D. Drives like normal otherwise.

Any tips or suggestions? Thanks!

 

How old is the alternator? Or is it original, if its original then the bushings maybe worn inside. A good way to diagnose this would be to have a good scan tool that data logs voltage. If its the alternator, I would replace with denso reman or oem or even used oem. I would avoid cheap aftermarket.

Things you can check for are worn battery terminals, make sure there nice and solid and clean.

 

I believe it’s the original. I’ve had the car since it had 63k on it and now has over 264k.

I’ve ordered a denso reman. I believe the alternator to be the issue. It tested around 13.5 to 13.7 voltmeters and I believe it should putting out over 14 from my understanding?

The battery is less than a year old and it tested fine yesterday. Everything looked clean and connections are solid. Nothing loose or corroded.

 

Then ya, its best to replace it. 13.5-13.7 is normal but what may happen is the voltage might drop intermittently and that would trigger a fault code. You may have worn brushes inside of the alternator. Known the less, its good that your going to swap out the alternator.