2008 IS250 with 47k miles, new battery one year ago:

Twice now I've been stranded. Unlock car with remote and then all is dead once inside. Car won't start. Doesn't even make the clicking sound. The first time things still lit up on the dash. The second time (today), it was completely dead... no dash lights, no buttons worked, not even the horn. After 30 minutes to an hour, it will suddenly respond and then start after hitting the button. Through all this, I've had AAA come and connect their device to the battery. It doesn't get the car started, but it gives me dash lights. Only an hour later will it respond to the ignition and start. At that point all runs fine, but my mpg's have reset to zero, so it's a hint all power was off to the car.

So I have no idea what the deal is here. The battery was new from Pep Boys a year ago and always shows a full charge when AAA is connected to it. Some are saying it may be a defective battery, but can that cause full accessory loss, even after I just drove it and shut it down minutes before it goes to full dead? Whatever is going on, it's cutting out immediately and not over a period of time. However, nothing has ever stopped working while I am actually driving.

If not that, a lose connection elsewhere? Bad fuse?

As of right now, it's got power again, but I don't trust it for the morning.
Thanks for any help!

 

Loose battery cable connection? Sounds like a possibility, as accessories would be powered by alternator when driving, but only sporadically powered (by battery-due to bad connection) when the engine is off.

 

Try with a brand new battery?

 

Thanks guys for replying. The story keeps changing each day. After a visit to Pep Boys Monday morning, I got mixed answers. They tested out the battery, alternator, and starter. All came out fine. The guy who did the alternator test showed me the printout. It said "13.55 under normal idle." Then when he gave it some gas and turned on accessories, the number dropped to "13.48." He handed me the paper and said all those numbers were normal. But then when his supervisor came by to see how it was going, that guy said right away the alternator numbers where bad and I needed a new one ($550). So two different responses for them. That didn't sit well with me, so I saved the numbers and drove home.

This morning I went to my regular mechanic (family friend) and he tested all three items as well. Each one passed with no problem or low numbers (I trust this guy, unlike the Pep Boys dude). So after trying to figure out what the heck could be causing the problem, he went back to check the battery connections and cables. One was loose. So he took it apart, cleaned the hole and tightened it all back down. I went back in to start the car and it was surprisingly dead. He reconnected his jumper, then it started, but died right away. I started it again a few seconds later and it turned on fine and stayed on. From that point on, he determined it was the loose connection. Car has been acting fine all day today since, but I still don't trust it. After he first tightened the connection, it died. After he jumped it, it came back. So something with that connection perhaps. I'm hoping however that tightening it down in the end will keep it going, if that is what the cause was. If this doesn't work, I'm going to have to take it in to Lexus who may have better testing methods. Was just trying to avoid the dealer charges compared to a private mechanic. We shall see, but so far it has been starting all day today.

So has any of this made sense? Having heard of what the last two places have done and said, do you think it could have been a loose connection afterall? Thus far two places have tested the major components and both said all were working fine. The odd thing with all this is between two AAA jumps, Pep Boys, myself and my dad all looking at this, no one detected a loose battery connection until the family mechanic today.

Thanks for your time on this.

 

^Just a small comment about what you mentioned above. After the mechanic disconnected the battery, rebuilt the cable to the battery, and then reconnected it you mentioned the car "started" momentarily and then died. This is normal. This always happens to any 2IS where the battery has been disconnected for like a few minutes or more.

Wish you luck on your electrical gremlins.

 

I just had that happen to my wifes car....Toyota highlander...All the gauges went crazy...Power/electrical steering went out.
It was the Alternator!

 

Thank you so much for that insightful info. That one turn of event really threw me off. We both thought we were on to something when he discovered the loose terminal and reconnected it. Then when I went to start it right after and it died right away, I was thinking to myself we must have done something or skipped right over the core problem. But now that makes perfect sense.

 

Update today. I spoke to the former head of mechanics who used to work at a Lexus dealership. Explained to him what's been happening. The first thing he asked was which brand battery I had. When I said "Bosche," he right away figured it was another defective battery. Said he saw a lot of problems with those when he worked at the dealership. I went on to explain all the other symptoms and what I've done to track things down, and he then said it could have been a loose terminal. He was very informative and really sounded like he knew his Lexus stuff. His suggestion to me was to take it back to Pep Boys and ask them to replace it for an Interstate battery. If I get one more dead car start, that is what I'll do. In the meantime, I'm hoping it was just that loose terminal we tightened up Monday.
Thanks all for taking the time to reply. Very helpful.

 

^^^^I've had two Bosch batteries in my F. I now have the Bosch AGM. Absolutely nothing wrong with them. You could have received a defective one, but if they read good when tested, that isn't the issue. BTW, Pep Boys doesn't carry Interstate. I know of no issues with members of this forum who have Bosch batteries. Or with my local friends who have them. I'm assuming that your alternator checks out?

Lou

 

That is good to hear. I too had never heard of mass problems with Bosch batteries. They are a well known brand with a long reputation. I was confident when I first signed up for this battery. After everything, I am still hoping and thinking it was a loose terminal.

Alternator and starter all checked out fine. So did the battery. It has to be the terminal, unless it's some other strange electrical issued buried deep in the car's computer.

 

Alternator should charge 13.9 to14.2v when you give it a rev get a multi meter and check it.

 

I have a somewhat similar problem. Whenever I press the Engine Start Stop switch the first time, the radio (if it had been left on before) and the clock come up. When I press the switch the second time, the dashboard lights do not come up. That means and it is a fact that nothing else in the car works. The red light of the switch flashes endlessly unless I press it again and, then; all the lights go off (the radio and the clock). At the dealer, they said the problem was a bad connection of the battery cable connectors, then, they said it was the battery itself the trouble maker. After that they said it was the Start Stop switch. Then, they said it was something else related to the dashboard itself and that it will cost me around $5000 dollars to fixed. During all that time, the car (Lexus IS250 2009) sometimes started and sometimes it didn't. I used the car when it started and only for round trips (no stops) until one day I had the car parked in my house parking lot; but running for a long time.. (maybe 2 or 3 hrs) with the purpose of fully charging the battery and making better connections in the electric system of the car. Unfortunately, when I turned the car off and on again, it did not go on.,, and it has not gone on now for a very long time. I have not used the car for over 8 months. I am discouraged and not comfortable taking the car back to the experts. I have paid them for all their diagnostic and assessments and repairs and the car still does not work. I am hoping someone here could help me and recommend what I should do.

 

Yikes, that's bad. It is the dealer's job to get things fixed when you take it to them. If they have looked at other things and charged you for those services, they owe you now to fix it. They have already taken your money and not lived up to their obligation. Maybe you have another dealer to help you. We are fortunate here in L.A. to have a dozen dealers to choose from. I will take mine to my best dealer if the problem persists. So far this week it has started every time. I am for now going to conclude it was a loose battery terminal that three mechanics never caught.
Good luck and don't give up! It's a great car, you just have to get this worked out.

 

^^^^Over the years what has worked for me with battery terminals is:

1. Use a terminal brush to clean the terminals on the battery and on the cable if there is the slightest bit of corrosion. Note - a terminal brush is a 2 piece affair that will clean both the outside of the terminal and the inside of the cable connector.

2. Make sure the terminal connectors are tight, but don't over tighten. The bolts are' made of pot metal and will break if overtightened. A washer will help maintain tightness.

3. Once the connection is tightened, apply a thin coating of Vaseline to the to the terminal and connector. This will help avoid future corrosion.

Lou

 

i went to pep boys too... they gave me same kind of battery and told me my fuel pump was the prob. So after changing my fuel pump my car still doesnt start always. It seems like it will only start between 2-5pm everyday and where ever it is that i turn it off its stuck there until the the next day in the sunlight... wtf?