Chevy Colorado & GMC Canyon banner

TPMS system issues

280 views 8 replies 3 participants last post by  Xcanuk  
#1 ·
Ok, so, yesterday I lowered the pressure from the 45PSI I had been running for my trip to CO back down to the recommended 36PSI. I used my digital Jaco gage I keep in my toolbox instead of the same one I keep IN the truck. On a cool morning in the garage, I lowered them to 36.0PSI. Got in the truck, and got warnings of low pressure, they TPMS was reading 3-4PSI low. I did the TPMS re-learn and drove it at decent speeds for a couple miles, and the readings went to 35PSI. Went back to the garage and checked the pressure of one tire again with my Jaco and got 38.0PSI. Made sense, since I'd been in the sun and driving it, so I then checked that same tire with the digital Jaco I keep in the truck and got 38.0PSI. So, that tells me the Jaco's (I bought 3 of the same model) are VERY consistent, and I can't imagine THEM being off. So, I tried the TPMS relearn again, and STILL got warnings. I said f@ck it and just drove to the BMW and Aud dealers, and then picked up some Midland Walkie Talkies for wheeling at Sportsman's Outdoor later. Warning on the dash the whole way and had to clear the 4 errors every time I started it, but the last time at Sportman's when I went to go home, it told me that the TPMS system needed service. So, something ain't right. Bummer, because Zed has been so good lately, and I'm bring him to work next week to show a buddy while I look at his new BMW X4M.

Later today after food shopping and maybe riding, I plan on checking the 2 Jaco gages to the digital Jaco inflator/gage I have on my compressor and see how that matches up. I can't imagine it being a problem with the Jaco's. I'll post my results.
 
#2 ·
Don't forget the conversation we had recently about elevation affecting the gauge reading as you get higher in elevation. A TPMS service warning is definitely different, but if you're at 6000ft elevation then your gauge is going to read roughly 3PSI higher than what the TPMS shows.
 
owns 2017 GMC Canyon Denali
#4 ·
The elevation is the same (my garage) from when I raised the pressure to 45 before my trip, and when I lowered it to 36. Now, barometric pressure (same effect as elevation) may be a bit different since it's been rainy here and cooler, but still, I don't think I should be getting errors when it tells me they're all 36 after driving on the highway for a while. Also, if it's only down a pound or 2, I wouldn't think it would read that as "low". The last time I got a REAL warning (bad valve stem) I think it didn't give me an error until it was like 26PSI, down from 36. I'm going to check the pressure with the 2 Jaco gages and my Jaco inflator/gage tomorrow and see. I may also use my couple year old manual Accugage (the brand I'd relied on for probably 30 years) and see what it says too. I tend to think something's wrong.
 
#3 ·
I'm missing something, you target 36 psi, but your guage shows 38, and the TPMS shows low? ( What pressure is the truck telling you ?). I thought the truck only triggers the light when more than 5 below recommended.

If all 4 are low, I'd try a hard reset (battery) first before troubleshooting further.
 
#5 ·
The truck was telling me about 33-34 when my Jaco said 36. When I drove it and came back, my Jaco's both said 38, and I think the truck said 35, STILL with a warning. I like having the TPMS, but, if it's that far off, it's usefulness is very limited, ESPECIALLY if it's showing an error and being only 1PSI down.
 
#6 ·
When you look at the pressure on the tpms screen, do all the numbers appear in red ? (Or some alternate color)
I have a gut feeling its a general tpms system error triggering the light. ( Hard reset before dealer )

I never found any tpms pressure 100% accurate more than within a pound or two, mine is metric which has no numerical retention in my brain, I just glance for pressure differences and if one is obviously low.
 
#7 ·
The entire TPMS screen is basically a bright orange now, so, SOMETHING'S wrong. I think it's not a pressure issue, but a TPMS system error.
 
#8 ·
Man, this system sure puts the "PMS" into "TPMS"... 🤣

Filled it up this morning to 38.0PSI via the digital Jaco inflator/gage on my compressor this morning, the TPMS was STILL showing 33-34PSI. Drive it for a while on the way to work, the pressure maxed out at 36PSI per the infotainment screen but the system STILL showed the warning on the dash and the TPMS system still showed in all orange. So, something's wrong, dammit...