I have a 2001 Lexus 430 with about 160,000 miles. I have had an ongoing electrical problem even though I have changed out the battery and alternator on multiple occasions. In the mornings, the vehicle usually won't start unless I get a jump from another car battery. (The jump, by the way, usually doesn't require me to start up the other car; the Lexus will start as soon as I connect the two batteries). I drive about 25 miles to work including the freeway. That will keep the car charged enough for me to start it during the day if I need to drive it. But the next morning, the same thing. I have had it checked out by three different mechanics, including a Lexus dealer, and they all say that the draw is within factory specs., and they can't find any specific issue with it. I'm thinking it may be a short somewhere that is the problem. Any ideas?

 

have you changed the drive belt, it's this that keeps the car battery charged from the alternator, if the belt is slipping or old then this can cause a problem.


I replaced mine a few months back aswell as the battery for a decent Bosch car battery and it's fine now. Before this the car would die within a week of no use. I would have to turn off the smart key access to try and save any juice in the battery.

 

Could your starter be going out?
It takes more electricity to start it?
I just changed out the starter on my Toyota and we thought it was the battery at first but a load test proved the battery was fine.
Some auto parts stores will do a load test for free.

 

Think I would check the drive belt or the alternator since the draw is within specs.

 

Sounds like your starter solenoid is going out. When they start to go, the starter needs a little extra juice, or a tap from a hammer to kick over. I'd let it cool, jack up the front, and have somebody try to start it, while i tapped on the smaller of the 2 cylinder shaped pieces of the starter. If you get it to kick on while tapping it, I'd say 99% it's the starter. If its the alternator, you'd usually get some goofy stuff going on with other electrical parts of the car or the car would eventually die after it sucked the battery dry of charge. If they have tested the battery/charging system and said it's fine, I would 100% suspect the starter is your problem. I would also make sure that there is good connection from your battery to the starter i.e. clean terminals / no corrosion. and also the small wire going to the solenoid has good/ clean connections. I' have seen some slightly dirty terminals cause this exact symptom before, and the extra juice from the second batter being hooked up was juuuust enough extra current going to the started to make it kick in.

 

Welcome to Club Lexus.

The simple places first, check the battery terminal cables to make sure they are clean and making good contact. I can only presume they tested the alternator and battery.

Any lights in-on the car that aren't working?
When you start the car is there any clicking?

My suspicion is the starter if everything else checks out: good battery, alternator. This is not an easy in-out job since it is located under the intake plenum.

 

All three don't work I've checked fuses and I'm not sure where to go let me know thanks