I recently had an unpleasant experience starting my 2nd trip of the day with my 7 month old (7,700 miles) TX 500h Luxury. Upon starting I immediately got scrolling error messages on both of my displays and my cell phone app (see attached) that all said "take the vehicle to a dealer". Because all of these sounded very serious (and unrelated?), I abandoned my trip to my doctor's office, and drove to my closest Lexus dealer (a 40 min drive). During that drive, the vehicle ran very rough from a stop to about 20 mph, then smoothed out, but would not go over about 55 mph and lost speed on an upgrade (no power!). As part of the journey was on an interstate (60 mph limit, but most traffic traveling more like 70-75 mph), I drove most of the way with my emergency flashers on (hoping I could make it without damaging something, thought about pulling over & getting a tow).
At the dealer without an appointment, they worked it in (service speculated that the symptoms sounded like a "low voltage" issue). The technicion that worked the problem said that he read, then cleared three OBD codes (P084000, P27C57F, & P08DE7F). He also worked a supposedly unrelated "Safety Recall" relative to the rear view camera that entailed "update the software for the Panoramic View Monitor System's Parking Assist ECU". He then test drove the vehicle and reported that the problem was gone. I've looked up the OBD codes, and they talk about a lot of potential issues from transmission fluid, press sensor, or TCM; batteries (both HV & 12V); alternator or inverter; etc., all of which are very serious!
The "problem" is gone and the vehicle does drive normally now, but because nothing was actually found or fixed, I'm worried about what was the root cause and when/if it will reappear (worst case scenario, a road trip in the middle of nowhere). Has anyone else experience anything like this, particularly on a new vehicle, and what does need to be repaired? Could it be just a software glitz and the firmware reload for the camera fixed it?? Because all of the "Vehicle Alerts" are for seemingly unrelated systems, this does sound like a vehicle ECU / software issue to me. I did mention to the service mgr. that one of the primary reasons we purchased the TX (1st Lexus) was the Lexus reputation for "reliability".
Those codes seem kinda random maybe the 12 volt battery is failing?
Sounds like it. I guess Lexus has a great deal on those 12V batteries since it's been failing on the RX and NX as well.
Also, I found the key can't be close to the 12V battery if you part in the garage. Put in a faraday box or pouch. These modern vehicle communicates with the keyfob quite often so it can drain the battery.
