I believe the fix was just making sure the connections were torqued down tight. I haven't had any issues since, myself.
Dead battery this morning (1 Viewer)
- Thread starter arich
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Markuson
SILVER Star
Ya, cleaning and tightening posts were the culprit on mine several years ago.
We had this happen a couple times with my wife’s Lexus GS 350. After going back and forth with the service manager, we figured out that keyless systems have some drawbacks, one of which is that the key connects to the car when it is outside of the car. We were putting our keys on the counter in the kitchen and it was just close enough to her car to connect. While nothing was visible, the car’s computer would turn on...and run the battery down. We now park the keys about 25 feet further away, and have not had it happen since.
bloc
SILVER Star
Another solution for keys activating is putting them into a faraday cage. This could be a special pouch you get from amazon, or even just a decorative metal tin sorta like an old school lunch box.
Plus this prevents your vehicle getting stolen via repeater attack..
Plus this prevents your vehicle getting stolen via repeater attack..
^ Like one of these, for example.
Amazon.com: Mission Darkness Faraday Bag for Keyfobs // Device Shielding for Smart Always On Keyfobs for Automobile Owners, Law Enforcement, Military, Executive Privacy, Travel Security, Anti-Hacking Assurance: Automotive
Buy Mission Darkness Faraday Bag for Keyfobs // Device Shielding for Smart Always On Keyfobs for Automobile Owners, Law Enforcement, Military, Executive Privacy, Travel Security, Anti-Hacking Assurance: Anti-Theft - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
amzn.com
Markuson
SILVER Star
Having a hard time making sense of the key proximity thing as a cause of that much drain. I’ve had my key in close enough proximity to be sensed...for several (undriven) weeks at a time in the garage...and never seen any perceivable drain due to proximity.
After my accident, my truck sat for months at a time...with backlit USB outlets always on...and months later, it fired right up.
Even if it triggered the interior lights as it does in a parking lot as you near the vehicle...those don’t stay on for long if the door doesn’t open.
I dunno...but seems pretty unusual if the FOB alone were to do that.
After my accident, my truck sat for months at a time...with backlit USB outlets always on...and months later, it fired right up.
Even if it triggered the interior lights as it does in a parking lot as you near the vehicle...those don’t stay on for long if the door doesn’t open.
I dunno...but seems pretty unusual if the FOB alone were to do that.
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I agree, but also agree there is something to this theory. I have to replace my key fob batteries every six months like clockwork. No clue why.
I have used Duracell, Energizer, special "hi tech electronics" versions of both brands. Makes no difference. My fobs are approximately 15' from the LC when I'm at home.
Haven't tried the faraday bags or further distances for storage, but at this point I'm willing to try! I realize this response isn't about the primary starting battery, but rather about the correlation to the fob / LC gizmos that might have something going on behind the scenes.
And, FWIW, others have suggested hooking up tech stream to check for subtle error codes, but I haven't gone through the effort of building/ finding a Windows PC yet.
Markuson
SILVER Star
Ya, don’t mean to suggest it’s wrong...more just that it doesn’t jibe with anything I’ve experienced with similar or long term proximity. Weird...
More recently, I keep stuff running/charging in my truck 24/7...and “plug in the truck” now at home. But it’s fine throughout trips and camping even when I’m in a tent 8 feet away with FOBs.
Super strange stuff...
Yeah, I was also doubtful when it happened to our Lexus. In talking to the service manager, he said the issue is that it fired up the car’s computer, which apparently pulls more power. Little car brain grinding away in anticipation of the car being turned on, but that doesn’t happen, so the battery just gets drained. He started with a battery replacement the first time it happened so it clearly wasn’t a common idea. By the way, like many others have noted elsewhere, this forum is awesome! Great folks just trying to help others and increase awareness and knowledge. Wish other forums I track had the same attitude.
My neighbor has a newer Highlander, less than a couple years old and he's had two batteries replaced because his car wouldn't start. Sent him a link to the faraday fobs, cheap potential solution might as well take it! There are actually a fair number of articles about this on the web, this one even references the issue @kevinfoutch is having, reverse parasitic draw. Today’s key fobs/smart keys provide convenience -- and cause problems - Automotive Service Professional
Hey guys, I have a 100 series with slee group 31 battery tray with the stainless extensions on the lead battery clamps.
I had a problem one time where it wouldn’t start, hooked up jumper cables and still wouldn’t start. Checked voltage on the battery and then on the lead clamp, then the stainless extension, and found I had a voltage loss where they’re connected. I’ve often wondered if anyone else has had that problem, so I’m glad to see I wasn’t alone. I also saw slee’s new billet clamps but that’s too rich for my blood. I was wondering though if they are because of people having galvanic corrosion issues with the old style.
I had a problem one time where it wouldn’t start, hooked up jumper cables and still wouldn’t start. Checked voltage on the battery and then on the lead clamp, then the stainless extension, and found I had a voltage loss where they’re connected. I’ve often wondered if anyone else has had that problem, so I’m glad to see I wasn’t alone. I also saw slee’s new billet clamps but that’s too rich for my blood. I was wondering though if they are because of people having galvanic corrosion issues with the old style.
CharlieS
GOLD Star
I bought a set of used, but never taken out of the package, slee billet terminals off facebook. These things are a work of art. I just installed them today.
I had a no start condition earlier this week. Both batteries read good with my multimeter. The aux battery relay latched, but the self jump didn't work. I clipped a charging clamp (not even connected to the charger) onto the postive lead and boom, the car came back on. Nothing seemed loose, but something wasn't making a good connection. I'm hoping these billet terminals will improve the situation.
I had a no start condition earlier this week. Both batteries read good with my multimeter. The aux battery relay latched, but the self jump didn't work. I clipped a charging clamp (not even connected to the charger) onto the postive lead and boom, the car came back on. Nothing seemed loose, but something wasn't making a good connection. I'm hoping these billet terminals will improve the situation.
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