No Power

[SultanOfSix]

I have an old 2006 Lexus IS250 that all of a sudden won't start. A few days ago, the engine was struggling to start. The next day, I tried to start it, and I would just hear a click, click, click. At that point I had power. I measured the voltage at 11.6 V which was low so it made sense why it wasn't sarting. I tried to jump it, but it wouldn't take charge. Now the car has no power at all. I took out the battery and took it to an AAP store to test the battery if it was faulty. It's only 2.5 years old and was still under warranty. They tested it and it is fine. I haven't been able to put the batter back in and try again because now the hydraulic supports on the hood started failing and it became dark. So I reordered new ones and will replace them, but I'll try to hold up the hood with something else and try the batter again tomorrow.

I've read that it could be issues with the ground connection or the alternator. How can I diagnose it without taking it to mechanic which means I will have to tow it there first since I obviously can't start it.

Thanks.

[RX400h]

Did the AAP person charge the battery and then perform a load test? Do you have a battery charger? Sometimes if you charge a battery and it does not accept the charge, it could have one or more dead cells, which means the battery needs to be replaced. 

However, if the battery can be charged to beyond 12 volts, and you can successfully start the car, then you should measure voltage while the engine is running. If the alternator is good, you should see over 13 volts. My car alternator outputs about 13.5 volts.

Make sure that the battery cable clamps are pushed down all the way before they are tightened. The connector's inside diameter and post should be cleaned with a wire brush tool that is made for this purpose. Once each clamp is tightened, you should not be able to rotate it. 

 

[SultanOfSix]

They did not do a load test. They just drained the battery and the charged it again and he said it was fine. I checked the voltage after he had recharged it and it was a little over 12.6 V. Sure, I can replace the battery and try again, but I would think that while 11.6 V may not be enough to start the car, then it would at least be enough to have power come to the vehicle so that the dash and/or inside lights would be working. But once I tried a couple times to start it after putting jumpers on and it didn't work, eventually nothing was working electrically in the car. At that point I took out the battery and wanted to get it tested.

But before I put the battery back in, I want to take some readings (if I can) with a multimeter to make sure that the ground connection is OK because if that isn't working, then if I connect the battery, it's still not going to start the car. Unfortunately, I don't know where to do that and was asking here for that help.

[RX400h]

I am a bit shocked that a load test was not done. How can anyone one for certain if the battery has enough cold cranking amps to start the car unless they do that test.

Regarding ground, if you connect the end of the negative cable to a ground connection other than the opposite end of the cable, and set your multimeter to audible continuity, the display should read zeros and emit an audible sound. That would affirm that the cable is grounded.

[SultanOfSix]

Status update: I got the battery charged again at an AAP store put the battery back in and the car started. So it ran for a few months with no issues, then just a few days ago the car wouldn't start on me again. Power came on, cranked, and then power went out. I checked the voltage in the battery and it read 11.8 V. So, now I think there is some electrical issue. I've read about a possible parasitic drain on the vehicle is possible. Once again, I took the battery back to AAP and they charged it again. However, this time I tried to start the car again, and now I am getting nothing. No power at all again, but the battery is reading 12.4 V. Can it still be a battery issue? Regardless, odd thing is when I connect jumper cables to the vehicle and try to jump it, it gets power, and cranks, but it won't start. So, with jumper cables and the other car running, the vehicle gets power. Disconnect the jumper cables, and use the connected battery, no power at all. Wouldn't that point to a battery problem then?

 

Thanks.

[RX400h]

It could still be the battery or your driving habits (short distance trips).

You can check for parasitic drain by doing the following:

Testing for Parasitic Draw with a Multimeter | Test Meter Pro