[Ailurus2SS]

So after going back and forth with electrical issues I'm stuck.

Last year I had the slow crank issue which turned out to be the starter like everyone else was having. After going back and forth with the dealership 4 or 5 times, they replaced the starter, starter solenoid, and the battery cable. On my own I bought a replacement battery from AutoZone. No issues for a year.

Now last month I made a trip out to PA, drove 100 miles, got to my rental spot and then went to the gas station for firewood. Went to start the car, it turned over, and then died a minute later. Tried turning the car on but the car was acting like it had no fuel. Luckily being at a gas station I thought maybe the reader was wrong so I put gas in and still nothing, wouldn't turn over so the car definitely has gas. I have a SCT BDX so I was able to read the code and it was all electrical stuff. U109 is the only one I remember but will add more once I get home and check again. Got the car to a mechanic and they replaced the battery. Issue went away

Now only a month later I'm having the same problem again. Sounds like the car is out of gas but I just filled it up yesterday. Same codes again but brand new battery. Ill disconnect the battery and bring it to AutoZone for testing and update with the other codes I had

[Sev]

Might be a dumb question, but have you checked the alternator?

[Ailurus2SS]

Originally Posted by Sev

Might be a dumb question, but have you checked the alternator?

Is there anyway I can test it at home? Or do I have to bring it to a shop. I would rather avoid the dealer after dealing with my many trips to just get a starter fixed

[ctrlz]

Originally Posted by Sev

Might be a dumb question, but have you checked the alternator?

Ding, ding, ding! Winner!

Check battery voltage at rest and while charging. What is the voltage meter doing while driving?
U0109 is fuel pump lost communication. If you got a bunch of other codes I would bet this is all related to low voltage.

Without more info, I think your battery is not being recharged properly.
You can get weird problems from an alternator where the car will still work but things are not right. I had a diode fail short years ago which introduced AC into the charging circuit. That was hard to detect, as they usually fail open. Typically 6 diodes in an alternator, so the 5 working properly sort of mask the problem.

Originally Posted by Ailurus2SS

Is there anyway I can test it at home? Or do I have to bring it to a shop. I would rather avoid the dealer after dealing with my many trips to just get a starter fixed

Start with a cheap voltmeter and youtube.
The alternator itself is hard to test. But once you know the resting voltage of the battery and the charging voltage you have a good idea if things are working.

[Ailurus2SS]

Originally Posted by ctrlz

Ding, ding, ding! Winner!

Check battery voltage at rest and while charging. What is the voltage meter doing while driving?
U0109 is fuel pump lost communication. If you got a bunch of other codes I would bet this is all related to low voltage.

Without more info, I think your battery is not being recharged properly.
You can get weird problems from an alternator where the car will still work but things are not right. I had a diode fail short years ago which introduced AC into the charging circuit. That was hard to detect, as they usually fail open. Typically 6 diodes in an alternator, so the 5 working properly sort of mask the problem.


Start with a cheap voltmeter and youtube.
The alternator itself is hard to test. But once you know the resting voltage of the battery and the charging voltage you have a good idea if things are working.

I definitely had a bunch of other electrical codes. About 3 or 4 in total. They U109 was the one I remember off the top of my head but they were all U01XX. I remember one was for my transmission and another was for brakes I think. I'll get the exact codes later today when I get home.

[ctrlz]

Just a link to back up what I'm saying. In case you go to the dealer and they say, "What does some idiot on the internet know?!"
Let's face it. Typically an alternator tests bad and they replace it. They don't investigate WHY it went bad.
https://www.knowyourparts.com/techni...-misdiagnosis/

[Ailurus2SS]

Originally Posted by ctrlz

Just a link to back up what I'm saying. In case you go to the dealer and they say, "What does some idiot on the internet know?!"
Let's face it. Typically an alternator tests bad and they replace it. They don't investigate WHY it went bad.
https://www.knowyourparts.com/techni...-misdiagnosis/

Screw the dealer lol they've done nothing but try to run my pockets and void my warranty. I'm going to bring the battery to AutoZone and see if they have a tool to check the alternator. If they don't, I'll order one but it seems that's the issue upon reading other stories. I'll update as soon as I can

[Ailurus2SS]

So far tried jumping the car by having a car connected to it for 10 minutes and it still wouldn't turn over. I check the codes and I also had U0121 for ABS and U0140 for BCM

[Ailurus2SS]

My device is able to read the ignition voltage and idk if it helps but it reads 11.3 V but when trying to start it, it drops between 8 or 9 V

[KirkH]

First thing to check is any aftermarket additions: tail lights, stereo power amp/sub woofer, led bulbs without resistor etc.

[KirkH]

Originally Posted by Ailurus2SS

My device is able to read the ignition voltage and idk if it helps but it reads 11.3 V but when trying to start it, it drops between 8 or 9 V

Should be 12.6 at rest. If not, the battery needs to be charged to start the car.

[Ailurus2SS]

Originally Posted by KirkH

Should be 12.6 at rest. If not, the battery needs to be charged to start the car.

I brought the battery to advance auto parts and they charged it for 30 min and said the battery was fine. The voltage on the dash shows about 12.5/13 v

[ctrlz]

Originally Posted by Ailurus2SS

My device is able to read the ignition voltage and idk if it helps but it reads 11.3 V but when trying to start it, it drops between 8 or 9 V

This is a severely discharged battery. It will not start a car. Hopefully your recharged battery has enough capacity to get you somewhere where you can test the alternator.
You are basically driving around with your battery powering the fuel pump, injectors, and everything else electric. That probably gives you a 30 minute range at most, depending on fan, lights, and other electrics that are running.

[Ailurus2SS]

Originally Posted by ctrlz

This is a severely discharged battery. It will not start a car. Hopefully your recharged battery has enough capacity to get you somewhere where you can test the alternator.
You are basically driving around with your battery powering the fuel pump, injectors, and everything else electric. That probably gives you a 30 minute range at most, depending on fan, lights, and other electrics that are running.

After they tried recharging the battery they said it was reading fine and I put it back and the dash read about 13. Car still wouldn't start