DTC P0514- Battery Temp. Sensor Performance/Rationality.

[Gr8tewhite05]

Has anyone had any experience with this one? Fixes?

 

[jelag]

I've researched this and have found a new one on ebay for about $22... I'm going to buy one and test it. . see which way the resistance moves as it goes from cold to warm... its to prevent overcharging of the batteries and my 05 went 7 years with the stock batteries and no water added over that period of time...

At 45* the charging voltage is 14. 4 and by the time the temperature is 85* its pushed back the charging voltage to 13. 4 or so... the key here is that the batteries never get above an 80% charge and trailer batteries never get above 70%...

This is great as the truck has the capacity to do well even at -30* and function... if you try and dry camp your trailer batteries are never charged and sulfate up and go away at 14-16 months...

I'm looking at 2 things... to fool the temp senor (thermistor) and better charge the batteries when we dry camp and/or install 250-300 watts of solar panels on the trailer so they are capped off all the time...

The converter on the trailer does the same thing... . starts to charge and tapers off... my controller doesn't have a circuit to prevent the batteries from sulfa ting up...

Hope this is what you were looking for... IMO its so that the batteries never need to be serviced and it extends their life by not overcharging... .

 

[rbattelle]

Besides what Jim says, that code is frequently encountered erroneously. It has a tendency to come up when ambient conditions interfere with the temp sensor reading. For instance, a strong wind blowing at just the right angle can cool the sensor and cause the code to trip.

If the batteries are charging, and the code does not continue to trip, there is probably no problem.

-Ryan

 

[Missouri Mule]

If your year truck is like the 2nd generation your battery temp sensor is under the driver's side battery tray.

 

[NavyDood]

I have had P0514 come and go over the past 7+ years. Living in the heat of TX or the chilly winters of MD, there was never a rhyme or reason as to when it would appear. I have never thought twice about it. I just clear the code and go my merry way. My truck was built Nov 03 and the original batteries are still installed and working just fine. I have also had P0480 (Cooling fan control circuit) come and go for the past 7+ years. Again, living in the heat of TX or the chilly winters of MD there was never a rhyme or reason as to when it would appear. My fan still works just fine cycling on and off as it should whether it is hot as blazes here in TX or in the chill of winter when I was in MD.

 

[jelag]

BTW - 3 gen sensor under the drivers side battery as well.....

 

[Road Dog]

This is great as the truck has the capacity to do well even at -30* and function... if you try and dry camp your trailer batteries are never charged and sulfate up and go away at 14-16 months...

I'm looking at 2 things... to fool the temp senor (thermistor) and better charge the batteries when we dry camp and/or install 250-300 watts of solar panels on the trailer so they are capped off all the time...

The converter on the trailer does the same thing... . starts to charge and tapers off... my controller doesn't have a circuit to prevent the batteries from sulfa ting up...

I think you're over thinking this. You can put a better charger-inverter in the the trailer (some have 3 stage changing plus maintenance) or you can hook up a proper smart (3 stage) charger at home once in a while. I don't rely on the truck to charge the camper battery.

 

[Prairie Dog]

You need to fill out a profile for your truck but I can tell you that early on in the third gens, there was a SW update that among other things, stopped the nuisance P0514.

 

[BK]

I agree with Red Dog.
The converters in the trailers and the alternator in the trucks/cars, are just bulk chargers.

Due to their lack of float charge capability, and terrible ripple on their voltage, they just don't treat AGM's very well at all. The wet cells do seem to handle the alternators on the Dodges much well.
(I got 7 years out of my OEM wet cells. I've tried top line AGM's, not fairing as well, I knew better but wanted to try. )

The trailers batteries , being so far back (long wires, ohms law ) don't charge well either when in tow, and the standard converters are terrible.


3rd party chargers with correct charge profiles for the chemistry, and once charged, a good quality maintenance / trickle charge is the way to go.
I haven't seen a bulk charger that has the quality float (trickle)(maintenance) charge as I've seen on the dedicated maintenance chargers.

The temp compensation is needed, and something we always designed in, or regulated the ambient temp for the battery compartment, for proper life / charge / and maximize capacity.

The issue I've seen with most automotive temp compensation, it's a snap function. . not the recommended slop for high and low temps.
Hotter it gets, the lower the float Voltage is suppose to be, and the colder the temp the higher the float voltage is suppose to be.

I don't know what the latest Dodge's are doing, but my 99 is like my 72 Dodge was... snaps up to 14. 6/14. 8 or so when it's cold. . normally 13. 8 .
No compensation for heat. They just beat the poor old cells up.

 

[AH64ID]

I've researched this and have found a new one on ebay for about $22... I'm going to buy one and test it. . see which way the resistance moves as it goes from cold to warm... its to prevent overcharging of the batteries and my 05 went 7 years with the stock batteries and no water added over that period of time...

At 45* the charging voltage is 14. 4 and by the time the temperature is 85* its pushed back the charging voltage to 13. 4 or so... the key here is that the batteries never get above an 80% charge and trailer batteries never get above 70%...

This is great as the truck has the capacity to do well even at -30* and function... if you try and dry camp your trailer batteries are never charged and sulfate up and go away at 14-16 months...

I'm looking at 2 things... to fool the temp senor (thermistor) and better charge the batteries when we dry camp and/or install 250-300 watts of solar panels on the trailer so they are capped off all the time...

The converter on the trailer does the same thing... . starts to charge and tapers off... my controller doesn't have a circuit to prevent the batteries from sulfa ting up...

Hope this is what you were looking for... IMO its so that the batteries never need to be serviced and it extends their life by not overcharging... .

My 05 never drops below 14ish volts and aside from grid heater ops I have never seen a 13. xx even on hot days after many hours of running. My trailer will see about 13. 6V at the batteries after a few hours of being towed.

Has your ECM software ever been updated? If not, I would get an update and I bet your charging increases. There was a TSB for this a few years ago.

Either way, 13. 4V should easily get the truck batteries to a 100% charge, 100% is 12. 6V.

 

[BK]

My 05 never drops below 14ish volts and aside from grid heater ops I have never seen a 13. xx even on hot days after many hours of running. My trailer will see about 13. 6V at the batteries after a few hours of being towed.

Has your ECM software ever been updated? If not, I would get an update and I bet your charging increases. There was a TSB for this a few years ago.

Either way, 13. 4V should easily get the truck batteries to a 100% charge, 100% is 12. 6V.

I hear what your saying, but don't think you meant what you typed... .

12. 6v isn't 100% charge, it's open terminal voltage if all plates/cells are there/healthy , and after residual have dissipated.
Open terminal and at a SG of 1. 265, it's 100% charged with 12. 6v (2. 1vpc x 6 cells).

If you set a charger at 12. 6vdc, it'll never charge the battery.

At 77degC, float voltage should be about 13. 6Vdc. Higher temps lower. Lower Temps higher.

Been trying to find a nice graph of the typical relationship of float vs temp online, but haven't. sorry.

 

[AH64ID]

I hear what your saying, but don't think you meant what you typed... .

12. 6v isn't 100% charge, it's open terminal voltage if all plates/cells are there/healthy , and after residual have dissipated.
Open terminal and at a SG of 1. 265, it's 100% charged with 12. 6v (2. 1vpc x 6 cells).

If you set a charger at 12. 6vdc, it'll never charge the battery.

At 77degC, float voltage should be about 13. 6Vdc. Higher temps lower. Lower Temps higher.

Been trying to find a nice graph of the typical relationship of float vs temp online, but haven't. sorry.

Yeah. . what you said

12. 6V without a charger is 100% charge, and my batteries have no issues holding that with the OEM charge rate.