2003 Toyota Camry with charging difficulties

I went to my local shop (which I highly respect and recommend) with a difficulty of a 2003 Camry having difficulties maintaining an adequate charge from the alternator. At certain times, the alternator starts slowly dropping charge down to about 9 volts. Not all the time. And it usually seems to happen after the Camry has been running for a while.

Once the situation begins after starting the car, it will continue to lower the voltage to about 9 volts and then keep it there while at idle such as at a traffic light, car pickup of children after school, in fast food lines, etc.

When you go forward again with the foot on the gas pedal, the voltage will also increase back to the normal range until you come to another traffic light, etc.

If you stop and let it idle for a while when the voltage is low and then decide to turn off the car, then the car may start with some difficulty or not at all. But if you continue to drive it and then turn it off, the car will easily restart again.

I have an inexpensive charge monitor in the 12-volt outlet which helps me track what it's doing between shop visits.

The shop I go to has tried a number of ideas but nothing seems to fix the random moving to a lower charge voltage even after three alternators have been installed. The first one was replaced, and then they tried a different brand thinking that possibly the rebuild plant which had rebuilt the first two alternators probably did so on the same day and may have had a production issue. The third one is from a second vendor.

It does have a recent battery from August. From the times that it was in the shop, they would have surely checked its ability to take and hold a charge many times over and the various battery and alternator connections would have been checked.

The shop has offered to fully refund the cost of my original repair ticket and which included diagnosis and alternator.

The question is: what would cause the alternator at random times start to provide a low charge, and then keep that low charge during idle and higher charge while driving? Whenever the situation begins, it continues until the car is turned off.

Thanks in advance for your insights.

 

What is the idle speed?

Any aftermarket items such as a stereo amp?

Any electrical items not turning off?

After the car sits overnight, what does battery voltage read?

What is the voltage at 2000 RPM when the low voltage problem happens and during normal operation?

 

toyomoho,

Thanks on the reply!

I'm more of an owner than a mechanic.

I think that I may have come across the problem. I went outside to the car and was going to remove a cable end for a minute to see if I could reset the car's computer and possibly get rid of anything which might affect the charging. When I went to use a small wrench on the ground connector to the battery, it was loose. When I tightened it a bit, I was then able to start the car with a full charge versus the not wanting to start a few minutes before. In short, I'm going to see how this holds out (or not).

But to answer your questions in the possibility that this may not have solved my problems:

What is the idle speed? I need to check.

Any aftermarket items such as a stereo amp? No.

Any electrical items not turning off? Not that I can tell.

After the car sits overnight, what does battery voltage read? I would need to check.

What is the voltage at 2000 RPM when the low voltage problem happens and during normal operation? I would need to check.

Sorry for the short answers and I see that I need to apply myself a bit more to the situation if the loose connector was not the problem. I'll know more over the next few days since it was sporadic in happening. Meanwhile I'll be collecting the data which you suggested.

Again, thanks for the reply and suggestions on what needs to be monitored next.

Dale

 

Just had a car having what may be a similar problem.

At engine idle the gear shift indicator dash light would slightly flicker. Had this issue for weeks. One day went to park the car and the electric assist steering was acting up as in hard steering. Went back to start the car 10 minutes later and electrical system was dead.

Turns out the negative battery cable connection that bolts to the battery terminal was very slightly loose. Moved the cable slightly by hand and the car now had power. Tightening the bolt solved the issue.

 

The charging system is working much better now and the battery along with it of course.

Per the newer circumstances, idle is approximately 650 to 675 RPM when reading the needle on the car gauge.

Voltage is usually about 13.8 to 13.9 but is now also above 14.0 a lot of the time.

Beginning voltage before turning the key is about 12.5 volts.

This morning with the 36 degree weather, the car actually started strong and smooth as opposed to before with warmer weather and a loose battery connection.

So far, so good. : )

 

Good job!

Thanks for posting back with the results.