desnard

I just had my battery replaced at the Lexus dealership. 4 days later my battery light comes on. Had it tested at Auto Zone which is showing a 17% charge and 11.9 voltage. Did the test where you remove the negative cable from the battery and the car died, which usually indicates a faulty alternator. Would Lexus replace a battery without checking the alternator? That just seems crazy. They went through the multi-point inspection but failed to test the alternator. The diagnostic report showed "bad cell" as the problem. This could have easily left me stranded or caused greater problems, like having my car die on the interstate. I'm taking it in Monday. Anyone have anything similar with Lexus service?

Clutchless

They were just sloppy and probably did not inspect anything beyond replacing your battery for a quick buck.
What year is your car? If you know you need an alternator you should shop price at independent repair shops vs the Lexus dealer. Even try the Toyota dealer.
Can't Auto Zone test your alternator? It only takes 20 seconds with the right tester.

desnard

It's a 2010. Auto Zone claims they can't do an official alternator test when the battery charge is that low, i.e. 17% in my case. According to my research, the test where you remove the negative cable from the battery while the car is running, and having your car die, indicates a bad alternator. Yes, I've researched the price, but I really want to see how they respond to this. Just wondered if anyone has been in a similar predicament and how they handled it.

Clutchless

Every dealer is different. You can't generalize your treatment to all Lexus dealers. I would complain to the service manager, or even contact Lexus corporate about the sloppy incomplete work at this dealer. They should at least give you a big discount on a new alternator for letting out of the shop with your car still needing repairs which they failed to notice. You have to complain and demand these things to get their attention. They hate to have corporate learn about these problems as it reflects badly and they can get spanked by corporate if there are too many complaints.
\aving said all that, I would never take a 10 year old car to a dealer to be repaired you are asking to get robbed. The mechanicals on this are common Toyota parts (engine, transmission, brakes, alternator, A/C, etc) shared wth millions of other Toyota/Lexus vehicles and almost any mechanic anywhere has repaired a Toyota and can work on the RX.

desnard

Yea, I typically don't bring my car into the dealer for service at this stage. I did this time, because the battery price was lower than several local repair shops. I always compare repair prices from dealer serviced and reputable repair shops. I've been finding that the dealer is really getting more competitive on their pricing. Actually, other than brake pads and routine maintenance, this will be the first repair....thankful for that.

lex_rx

Just wondering what the OP told the dealer to do.

I almost always go to the dealer for maintenance and repairs and one of the things that I read years ago and remind myself when bringing the car in for anything other than usual maintenance items is to not to tell them what to do but rather to let them diagnose. My 2011 failed to start on Feb 2017 and the CAA tow truck driver couldn't start it either. Dealer did a diagnostic for C$65 and the root cause pointed to a broken starter that was then replaced. The only time that I tell the dealer what to do and to skip the diagnostic or road test is when I'm pretty sure what the problem is. This is my second RX and wheel bearing has been an issue on both my previous 2nd gen and this 3rd gen. So when I heard the now-familiar wheel bearing hum, I told them to skip the road test and replace the wheel bearing.

And as the OP noticed, Lexus is quite competitive in pricing if competing garage use OEM rather than cheaper parts. Toyota dealers in my city and surrounding cities will not touch a Lexus and some independent "import" garages have certain services that are more expensive than the dealer, e.g. spark plug replacement.

salimshah

When you have shorted cell in a battery, the alternator diodes get stressed and potentially die.

Since you are having un-expected problems after the battery change, use the 6 months warranty [it may be 3 or less as it is elect. in nature]. I would say take to the same dealer and say the repair was no good and let them diagnose fully. There is a chance that you got a bad battery, or even flat-battery as they forgot to charge [lead acid needs to constantly charged when stored].

Repair at times requires dedicated sleuth work... why did the battery die or what impact the bad battery would have on the system.

Bench testing the alternator is not a difficult task and the box store should be able to do it, provided you remove the alternator. A quick charging test is something the shop should have done [but knowing they can't sell you one at this stage they may have little incentive to help .. specially in the COVID environment ... I have heard that the shops are no longer doing the OBDII readings as well].

If the diode(s) has died, you may like to entertain the though to replacing the diode pack and brushes. Easy DIY in my book.

Salim