I Looked at the tpms right after getting the new Outback. I swear it showed the tire pressures of each tire. Well today I thought to look again. It doesn't show any pressures.I was well over 20 mph, etc. I checked all tire pressures and they were AOK. So what gives?
Tpms not showing any tire pressures
1 reading
MadDad
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There was also a recent TSB issued for the TPMS and DTC2921..
05-78-20 Technical Service Bulletin
DTC C2921 ID Registration Error and Bit Translation Table for Use in Tire Pressure System (TPMS) Diagnostics
Oct 13, 2020
Probably more of the same stuff that’s in that techtips article.
Got our car back Thursday. They said they had to order 4 tpms units, and then replaced all four. Might take a couple of weeks to see if they continue working. Got my fingers crossed. Maybe mentioning the lemon law might have helped a little.
So far so good!!!!
It means one or more of the tire sensors are defective, usually a battery going bad or dying. If one goes out the system just reverts to that display. That’s how it was with mine and others on this forum. The dealer can find out which one(s) it is and replace it.![Image]()
I’ve never seen by TPMS like this. It’s been like this for about 50 miles and several key cycles. Normally they are a little Dash lines on each side before it acknowledges the actual pressure. Now there is nothing. Is this a known issue?
Old thread, but same problem. Bought my Outback yesterday, tpms shows dashes (--) for each tire. Somewhere in the thread I saw that you should drive a bit before the monitor kicks in. I'll check that tomorrow.
Sense they repleted all my sensors It has worked fine. Yes you have to go over 20 MPH for a little bit.
I'm having the blank display as well. How much is "a little bit" for over 20 MPH? I drove for 10 minutes at speeds varying up to 60 in traffic and lights -- still blanks.
20mph is as fast as you need to go. One bad sensor - low battery, defective, etc. - will blank the whole system. Only the specialized equipment which the dealer will have can identify the specific one, if it is just one. When I got my car there must have been a bad batch of sensor batteries - there were quite a few posts around the same time with this issue. Once my sensor was replaced over a year ago I haven’t had any issues. They are supposed to have over a 5 year life span. Once you hit 20 for a couple minutes it should read when operating correctly.
Thanks -- I'm using brand new sensors from TireRack, who I've also reached out to for comment. I used a Autel TS508 without any errors in the process (with the exception of skipping the spare).
Year & Trim level? And please tell us the whole story. When did this happen, what did you do prior?
Basic diagnostics are relatively easy if you have a good hand-held TPMS tool, as some of the regulars on this board have made a modest investment in. My Autel TS508 can read out each wheel sensor to determine their state of health, upload (register) that data to the vehicle, and read out TPMS DTC's to enable diagnostics.
Thanks for asking.
2018 Outback, 3.6R Touring (bought new from dealer in NJ)
This just happened today after driving around on the brand new winter tires (Blizzaks on steel wheels) with the TPMS warning light on for months. (Tires and wheels with TPMS sensors new from TireRack) I finally bought an Autel TS508, updated the software, ran the Position Relearn process and had no issues through OBDII. Ignition off; Ignition on, drove for about 10 minutes at varying speeds up to 60 mph. By the way, Autel TS508 had no issues and showed no problems with the sensor health. The only thing I can think of was that I skipped the spare because I can't find a sensor on my spare...
The tire pressure warning light extinguished as soon as the Position Relearn process completed, but the tire pressure page of the info display was blank for all four tires throughout the drive. Ignition off after the drive, then back on. Still blanks.
I've reached out to both Autel and TireRack for help. Awaiting responses further than their acknowledgement of receipt of the query.
Thanks, all.
Thanks for updating your profile with vehicle data.
OK, so 2018 uses the newer 433 MHz system with full dash display enabled by PAL (phase angle tracking during rotation). The TPMS RKE module only processes 4 hex codes, so even if you had a full size spare with a sensor, you could not upload the 5th sensor. Some 2021+ models have that ability, but not your 2018.
You own a TS508 and sound like you know how to use it. Software updated, confirmation including light off at the end which says the new codes were successfully uploaded and operation confirmed, no download of stored or new codes.
Did you get a flashing or solid dash light in addition to no LCD readout? I've not done it, but I believe you can query the system to see if there are any new stored DTC (it would be a mfgr proprietary Cxxxx, so most basic scanners will not see it).
And not that you should have to, but it wouldn't hurt to scan the wheels and re-register the codes. System glitches happen....
Curious: Did TR tell you if they used Schrader/Subaru OE 28103xxxxx sensors, pre-programmed Subaru aftermarket, or programmables that they imprinted with the Subaru protocol?
OK, so 2018 uses the newer 433 MHz system with full dash display enabled by PAL (phase angle tracking during rotation). The TPMS RKE module only processes 4 hex codes, so even if you had a full size spare with a sensor, you could not upload the 5th sensor. Some 2021+ models have that ability, but not your 2018.
You own a TS508 and sound like you know how to use it. Software updated, confirmation including light off at the end which says the new codes were successfully uploaded and operation confirmed, no download of stored or new codes.
Did you get a flashing or solid dash light in addition to no LCD readout? I've not done it, but I believe you can query the system to see if there are any new stored DTC (it would be a mfgr proprietary Cxxxx, so most basic scanners will not see it).
And not that you should have to, but it wouldn't hurt to scan the wheels and re-register the codes. System glitches happen....
Curious: Did TR tell you if they used Schrader/Subaru OE 28103xxxxx sensors, pre-programmed Subaru aftermarket, or programmables that they imprinted with the Subaru protocol?
Thanks. Will need to follow up with TR about that. They actually already shipped out a replacement sensor in anticipation that it might be just one that is bad and also requested invoice for replacement. Cannot say enough about how great TR has been throughout.
Autel also emailed and called me today in response to my chat query. They proposed a method of pinging but skipping the spare that wasn't addressed in manual -- walk ten feet away from the car, ping the non-existent spare, then press N and continue prompts. I still need to drive the 10 over 20 later today when time permits and will report back.
After following Autel's advice on the position relearn process, the pressures remained blank for three days (and about 100 miles) until the fourth morning when I was driving to the shop to get the wheels/tires swapped for the season and all four tire pressure fields populated with pressures around 33 lbs (approximately what I expected for the winter tires). One difference is that the all-season/"summer" tires on OEM wheels were also in the car, but diagnostics with the Autel TS508 showed that the OBD had the winter tires' codes, not the "summer" tires' codes.
After swapping the tires and following the Position Relearn procedure on the Autel TS508 with the OEM tires/wheels/sensors, all appears to be working fine with pressure readings populating the fields. Now we wait until next winter to see what happens when they're swapped.
Thank you all for your interest and help.
We are all still learning about the peculiar nature of these systems. If the Autel sensors keep the dash light off, they are meeting basic requirements of broadcasting all the required information. Perhaps it's an interval thing (not often enough) that in conjunction with PAL isn't satisfying the requirements of the on-board system to sort out which ID is at which corner, and so it can't reliably populate the dash display. Just conjecture....
Keep us informed on future events!
Keep us informed on future events!
Brand new 2024 wilderness with only 700+ miles now. I first got a warning that the pressure was low about a month ago but my tires were fine and the pressure was good. Now 2 days ago I got the warning again and all pressures were fine. Now I am not getting any reading over the last 5 drives and all were over 20mph. I must have a sensor that is bad or a low battery.
Dont the new tpms readers now days show the battery levels of the sensors? I thought about just going to a tire shop and see if they could check it and determine is its only a certain one.
Dont the new tpms readers now days show the battery levels of the sensors? I thought about just going to a tire shop and see if they could check it and determine is its only a certain one.
23 Ascent Premium & 20 Outback Premium; former 19 Outback Premium, 85 GL Wagon, 87 GL-10 Wagon
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That new just let the dealer fix it under warranty. Though not common sometimes a new sensor is bad.
I dont trust the dealers very often and like to go there with as much information as possible. If I know exactly which sensor is bad or low battery I can let them know.
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