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With all the dead battery threads, I bought a voltmeter that I leave plugged in. When the truck is running, it has consistently stayed around 14.6ish, recently it seems to be creeping up to 15.3. Is this too high?
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15.3vdc is about a half volt high, but then how accurate is your meter? Over charging a battery creates more heat then normal charging, should be no more than warm.
I've got 3 meters and they all read a little different but never over 15vdc on a car battery.
I've got 3 meters and they all read a little different but never over 15vdc on a car battery.
Apparently not. In line with my Hybrid lariat. With most of 12v stuff not active it may get as low as 13.2. I only once saw this low though it could possibly get below that. 14.8 is largest I have seen without cabin heat on and with seat heat and steering heat on it will be 15.3. I don't know what max is but 15.3 is most I have seen. If you turn truck off and when no draw is on (lights, bed, radio timed off the voltage reading will show 12v soc reading and will be 12.1 to 12.8 (=12v deep cycle battery soc 50%- 100%). (Good to see if your 12v battery is charged). Very seldom will you see 12.1 anything less apparently turns on 12v charging as the reading will go to 14.7-14.8 with some variance (+/- 0.1v,) depending on the accuracy of your meter). Note that a lot of the power point phone chargers have high voltage protection maybe at 14.5volts and if so will not charge your phone if the bus has 14.5 or more voltage on it.
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Mine also tends to charge around 15v. ForScan reports 14.93v is being commanded to the DC-DC converter, measured at the battery itself it was about 15.04v (so I guess I know my battery harness has good connection).
My Kicker Key 200.4 and the original Pioneer I had for my subwoofer are/were fine with it, but I actually discovered this high-ish voltage when my Pioneer died and I replaced it. 15v is right around where some amps will shut off for voltage protection. So some days my new amp would work, other times it wouldn't. It was driving me crazy thinking it was something with the signal detect auto turn-on but persisted even after running a remote wire. Even stranger it would work when I opened a door, but shutdown when it was closed. Then I realized it might not be lack of power but too much power and in particular for whatever reason when a door is open the DC-DC converter is commanded to only ~13.6v. My fix ended up just being putting a fat rectifier bridge in the power feed to the subwoofer amp. It technically doesn't do anything since it's already DC current, but it was the easiest way to have something that could pass a bunch of current and the little bit of voltage drop through the diodes keeps the amp in its happy range.
Technically 15.5v isn't uncommon on some new vehicles even with alternators. The BMS on them wants to recharge the battery with the power used to start and then will drop way down to as low as 12.8v. This gets the parasitic load off of the engine as soon as possible so MPG is better.
My Kicker Key 200.4 and the original Pioneer I had for my subwoofer are/were fine with it, but I actually discovered this high-ish voltage when my Pioneer died and I replaced it. 15v is right around where some amps will shut off for voltage protection. So some days my new amp would work, other times it wouldn't. It was driving me crazy thinking it was something with the signal detect auto turn-on but persisted even after running a remote wire. Even stranger it would work when I opened a door, but shutdown when it was closed. Then I realized it might not be lack of power but too much power and in particular for whatever reason when a door is open the DC-DC converter is commanded to only ~13.6v. My fix ended up just being putting a fat rectifier bridge in the power feed to the subwoofer amp. It technically doesn't do anything since it's already DC current, but it was the easiest way to have something that could pass a bunch of current and the little bit of voltage drop through the diodes keeps the amp in its happy range.
Technically 15.5v isn't uncommon on some new vehicles even with alternators. The BMS on them wants to recharge the battery with the power used to start and then will drop way down to as low as 12.8v. This gets the parasitic load off of the engine as soon as possible so MPG is better.
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Also read manual on battery replacement. There is an 8 hour "battery learning" procedure that is to be ran with accessories turned off and truck locked undisturbed during this time. Apparently this determines if you have a flooded cell or a battery that is chargeable to different parameters than the battery being replaced. Also states that procedure might need to be done if battery is improperly charged by out of vehicle charger.
It can also be manually performed by turning key on, flashing highbeams 5 times, and pressing brake pedal 3 times. After some seconds the battery indicator on the dash will flash a few times as confirmation.
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Oh heavens yes that would be unsafe except in rare circumstances. But Ford is now a battery company that makes Truck like Tesla but with Trucks.
They have a brain trust in batteries and used research and testing to give us a Hybrid with 1/6 less battery than originally planned because they can tightly control the normal un tapped capacity of chemicals at the upper end of the thermal range. They by default run batteries at the unsafe heat a simple consumer grade charger would refuse.
As another poster pointed out that voltage would heat the 12v up, that is the goal. The charger in the Hybrid is robust and can push amps to what the battery can absorb. Which is helpful in all common situations. Cold short trips no problem slamming the 12v to recover as quickly as chemically able ( which increases with temperature)
They have a brain trust in batteries and used research and testing to give us a Hybrid with 1/6 less battery than originally planned because they can tightly control the normal un tapped capacity of chemicals at the upper end of the thermal range. They by default run batteries at the unsafe heat a simple consumer grade charger would refuse.
As another poster pointed out that voltage would heat the 12v up, that is the goal. The charger in the Hybrid is robust and can push amps to what the battery can absorb. Which is helpful in all common situations. Cold short trips no problem slamming the 12v to recover as quickly as chemically able ( which increases with temperature)
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So I did this last Friday and today was the first I’ve driven it since. My same work commute and it stayed at 14.8 both directions. I’m not sure if that lowered it from the 15.3 or if it was because the temperature difference. Last week it was in the 30s and 40s, this morning it was in the 60s.
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I only have a voltmeter that plugs into the dash. I will admit that I am clueless about this so please excuse my ignorance
A little tricky with the dash monitor but that is what I am using with my lariat. Which hybrid do you have.. with my lariat. After my drive I leave monitor in dash power point and just push the ready button once and without doing anything do not open door. Wait until things power down lights go off (30 seconds?). The monitor should show what voltage the 12v I putting into the buss. Mine will display 12.1-12.8 volts. (Depending on SOC of 12v). When getting into truck in am get in shut the door. Push the power point monitor in to turn it on and read the SOC. OF 12v. Then you can push the ready button which will ready the truck and the voltage monitor will jump to 14.8 and turn on all 12v items. I have not checked my XLT That has a key but I expect to just turn the key to accessory without for enought into the spring portion to "start" truck. I expect on hybrid this will show the 12v SOC Since you haven't started the truck.
To clarify. I am catching the 12v dash power point without the dcdc converter active on the. 12v buss.
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