Tire Pressure Monioring

[TalkeetnaDodge]

2012 1500; In Alaska; temperature dropped to -10 last night. This morning TPM alert came on - Front (left & right) indicated 30 psi; Rear left 30 PSI and Rear Right- mostly no illumination, an occasional flicker indication (30psi) (otherwise no illumination of numbers etc) Latter today, RF,LF, & LR all showed 32 psi in warmer temperatures. I checked pressure in each tire with guage - LF, RF, LR, & RR - all indicated around 35 psi (I need to check door post again). Also, orange check light illuminated.

Any ideas on why there is no illumination for right rear tire? If I reset orange check light, will it re-illuminate becasue of no reading on right rear tire? Does anyone know, if there is a replaceable battery in TPM sending units? This is my first go with such a system and educating myself about nuances. Comments appreciated.

 

[Bigskyroadglide]

The tpms sensors, one in each tire are battery powered, if you have one not registering or showing dashs in a specific location it might be time to replace them. Factory sensors will generally last 8 to 10 years. The battery is built into the sensor the battery is not replaceable, but does screw onto the valve stem

If you have flickering on the dash, you might need to eliminate the sensor before you dive into dash issues. The receiver for tpms sensors is located in front of the left front tire and sometimes has issues when exposed to lots of mud and snow.

YouTube has got a few good videos about rams sensors.

Last, you have the old system of sensors if you have a 2012 truck. They require a different sensor than the 2013 up trucks. Your best solution is to get the sensors from Ma Mopar. Be prepared they are overly expensive.

Good luck, I learned more about the tpms system with my 2011 truck than I care to admit fighting aftermarket sensors. The good news is the truck works whether the tpms sensors work or not.

Or if you have alfaobd, you can see if you can disable the function. I never wanted to take that direction

PS. I live in Montana, I run my tires at 40 psi in the winter. They can fluctuate 4 to 5 lbs depending on temp

 

[TalkeetnaDodge]

BigSky; Thanks for the detailed reply. The 'cold' temps are here for another week now up to 5º. I am noticing a fluctuation between 30 psi to 33 psi. The right rear indicator blinks on and off at about the same psi.
I will try upping the pressure a bit in each tire and then reset the warning. Funny: three gas stations whe air is available - none of the compressors work - so this makes what should be simple, more 'complex' I do have a bike pump! I will check out that supplier - this electronic stuff - it doesn't make sense to replace/trouble shoot otherwise until winter tires are off for summer ones (PITA), but will start planning, etc.

 

[jws123]

My tire light on my 2011 was on for 6 years Lol just check your pressure every once in a while and ignore the light. It is a pain in the ass system to deal with not just with rams I deal with it every single day people come in with tire lights on.

 

[Wild one]

BigSky; Thanks for the detailed reply. The 'cold' temps are here for another week now up to 5º. I am noticing a fluctuation between 30 psi to 33 psi. The right rear indicator blinks on and off at about the same psi.
I will try upping the pressure a bit in each tire and then reset the warning. Funny: three gas stations whe air is available - none of the compressors work - so this makes what should be simple, more 'complex' I do have a bike pump! I will check out that supplier - this electronic stuff - it doesn't make sense to replace/trouble shoot otherwise until winter tires are off for summer ones (PITA), but will start planning, etc.

You can buy portable 12 volt air compressors fairly cheap,being in Alaska,you probably should have one.

Amazon.com : 12 volt air compressor

If you want to kill 2 birds with one stone,the majority of these 12 volt jacks also have a built-in air compressor.

Amazon.com : 12 volt car jacks

This one even comes with a cordless impact gun.

https://www.amazon.com/dp/B09Q5C4Z96?ref=emc_s_m_5_i_n

 

[Curmudgeon]

Whatever you do make sure the air you put in your tires is at least 78% Nitrogen

 

[62Blazer]

Not sure if this is part of the question or not, but the pressure in the tires will fluctuate with temperature. Meaning if you inflate the tires to say 35 psi on a day that is 70 F, and the next day it drops to 20 F the pressure will be lower. There are multiple factors but generally about 1 psi per 10 degrees. So if the temperature dropped 50 F overnight I would expect to see around a 5 psi drop in tire pressure. When you drive the tires generate heat and warm up, thus why the pressure increases as you drive.
There is a certain level that the tire psi can drop from the set pressure before the light sets. For example, if the tire placard inside the door wants 35 psi in the tires, the warning light usually doesn't come on until the sensors read maybe 30 psi or less (varies by manufacturer and vehicle). Now while the warning will not come on until the tires drop from 35 to 30 psi, it usually won't reset until you pump them all the way back up to 35 psi.
As already stated, if you have one flickering my first suspicion would be the battery in that one sensor is getting low. If they are still the original sensors they are getting old and would expect the batteries to start going bad. The fact that it is getting colder makes the condition worse as batteries lose power as the temps drop. Go to a tire shop, tell them what is going on, and see how they would charge to change the sensor. This is something that any decent tire shop deals with on a regular basis and should be able to fix it. Most likely they will slap another sensor in it, and probably have the right one sitting on the shelf.

 

[Dean2]

The guys provide good advice. I fill my tires to 50 PSI at 0F. At 50F they will have 55 psi, at -50F they will be 45 PSI. I just live with the + and - 5 psi fluctuation because it is a pain to keep them any closer than that.The light on the dash flickering can be a function of the cold. At -40F some of my dash lights don't want to light up, once the cab warms the lights come back on. 2021 Ram 2500, many of the dash lights are LED and it seems some LEDs don't like real cold weather all that much.

 

[TalkeetnaDodge]

Thanks for input. As a former commercial pilot...I have had to retrain myself to ignore automotive warning lights, etc. I checked tires: 40 psi. The local temps will warm up to mid teens next week and I will see what happens. In the interim I do a 'preflight' walk around and kick the tires!