Lexus electrics

A friend has a 2001 Lexus 300 small 4 dr. small sedan. Over 200k miles Over a period of several recent years, Lexus replaced at least 6 batteries on warranty without finding the problem. Another friend took the car to a national chain garage, who has replaced the alternator and battery 3 times on warranty, but says they will not do so again. What gives

Depends on what the problem is. What, exactly, is going on? What are the symptoms? Lexus (Toyota) don’t have any more electrical problems than other brands, on average.

If those 2 things have been replace, it only leaves cables. I would clean the grounds and check where the battery connectors are. If there is green or white powdery stuff under the rubber insulation, replace the cables.

It also leaves the starter, so understanding what is the problem is the first step.

I have to think there is some misdiagnosis on this problem. Either the batteries are being misdiagnosed as bad with the real cause being a parasitic draw or charging issue OR there is something like an overcharging issue which is killing them and is not being diagnosed correctly.

It baffles me that Lexus would warranty that many batteries because after a few stabs someone usually starts asking questions and will start denying claims. All assuming the batteries were actually replaced and there was no placebo being given.

There’s apparently 3 people involved in this so the water gets a bit murky.

So, how often and how far does your friend usually drive?
One cause of repeated dead batteries is failure to drive the vehicle far enough to recharge the battery after starting. Since the cause isn’t technical in nature, techs can never find it.

There are, of course, other causes such as parasitic drain and failing alternators, but I’m assuming those have all been checked more than once.

The car apparently needs to go to a reputable independent shop for a proper diagnosis and repair

That more than likely won’t happen at a tire chain

It’s sad that nobody at the dealer was able to figure it out

I suspect the guys at the dealership are young, just out of trade school, and have neither the patience, motivation, or the diagnostic skills to resolve the problem once and for all

This is a job for a veteran wrencher, not a bloody beginner

A better description of the actual problem would also help

Battery is not being charged while driving?

Battery goes dead overnight?

A lot of these problems can be traced back to parasitic electrical drains that discharge the battery in a matter of a few days…Alarm systems, remote starters, keyless entry, GPS, Bluetooth capability, computer controls that are always on, these things can add up to a considerable load on the battery and depending on how the car is driven, the alternator just can’t keep up and the battery fails prematurely…

If I read this correctly he has put in 9 batteries and 3 alternators!!! The Toyota alternators usually last 100k+. The es never had any eletrical issues beyond the trunk harness. Does the car sit for extended periods of time or have any aftermarket accessories that may be causing a drain? Like stated above check the battery cables are the factory terminals still present or have the cables been modifyed? If all looks good there do an amp draw test.

Please see 1998 Lexus ES300 eletrical May 25 2014. sounds like related problem. The 2001 starts by battery going dead over night and progresses to killing the alternator. No electrtical additions have been made

I had a problem with frequent battery discharge on a VW Jetta. Dealer could not find anything.

I finally guessed that the overhead light, which stays on a few minutes when you leave the car, was occasionally never turning off, draining the battery. I turned the light off, never had another battery problem

b

See new discussion Lexus Electrical new Sept 2014. marcello

Keep it simple @Marcello; starting a new post about diagnosing the same problem and people will stop commenting.
On your new post, everyone is going to start asking the same questions that they asked in this one.
So please keep it to one post until we figure this problem out.

Yosemite