Leaving work this AM, my 2011 RAM Big Horn 4X4 gave me a low tire pressure warning. The screen is flashing 3 out of 4 pressure values even though the 4th value is just as low. All tires are measuring 38lbs with the screen saying 31 on driver side & 30 on passenger side. Drove it around to see if the sensor would reset, no luck. The temp got down to 32 degrees last night, which isn't that cold here. Any thoughts?

 

Increase the pressure by a few pounds and drive it a little, then decrease it a few and drive it a little. If you don't get any change you may have bigger isues than a sensor.

 

I had this issue last week and have had it in the past at the first sign of colder weather. I increased the pressure to 40 on every tire and drove down the road a little bit to get the light off. I have noticed these sensors are pretty sensitive and will go off even with a just a few lbs of difference.

 

I have a early build 09 and mine goes off when pressure drops below 30psi. ( usually once on the first cold morning, then I top them all off. Fill it up to 35 and it shuts off.

 

Seems like when they hit 29 they go off. It got cold here one morning and one tire was at 29 -the light went off.

I aired them up to 38 and no more issues.

 

Going into the 3rd winter with this truck, I was surprised by the low tire pressure mess. Especially since the last 2 winter we saw negative temps! Couple that with the pressure gauge on my air hose reading high... what I thought the tires had, actually did not. Went old school with one of the little cheap pressure gauges, & sure enough... it read better & more accurate than the fancy ones! Thank you for all your replies! Much Appreciated!!!

 

yes i have the same problem with the gage on my tire filler reading high (says 34-35 and its actually about 30-31) so i was annoyed by the sensors, especially on our van. if the truck says 30 and your gage says 38, i would get another gage or get your gage checked. if thats not it, then maybe an issue with truck or sensors.

i am curious if the cold actually affects these sensors, or if its just that the cold will cause the pressure to drop a little.

 

FYI to anyone interested. On most of these systems, the threshold for low/high can be changed with a scan tool. The default is usually 28 psi low and a differential of 6 PSI fromm lowest to highest.

 

Really? Mine doesn't go off on the high side until around 42psi

 

Change over to nitrogen filled tires, solves ALOT of problems.
Google it, lots of info about nitrogen filled tires and why its better. (or is it...?)
Only benefit i see out of it, TPMS is always the same pressure year round... good enough reason for me.