Random Tire Pressure Warnings even though pressure is right.
05-28-2023, 10:33 PM
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2005 SL500, 2008 CLK350, 2013 S550 Weistec
Random Tire Pressure Warnings even though pressure is right.
Hi Team,
My wife's CLK350 (2008) has been getting on her nerves and in turn she does on mine. The car is constantly bombarding us with any random permutation of "Please correct tire pressure", "Tire defect" etc error messages on the dash. Wheels are perfectly balanced and inflated properly, and from what I understand this is not a 'real' or active TMPS system, it just looks for fluctuations compared to the default values, I suppose somehow by looking at wheel rotation speed. I've checked my specs and this is supposed to be a "Low Line" monitoring system, no run flats or anything like that - which would mean there's no actual pressure sensors inside my tires, but I've never looked inside.
I've tried resetting the TPMS system through the dash but the errors came right back in a few minutes. Any ideas? Thank you so much!
Edit: after a bit of chatting to my tire guy it turns out I _do_ have an active sensor system, but now my main question is why the baseline values wouldn't update when I reset the TPMS. The card in the door jamb says 28 PSI front, 35 rear. I've been running this exact pressure for years, suspension is aligned to these values too. If I inflate the tires to exactly this spec the errors never stop, and when I plug in my scanner it says both front and rear axle baseline values are 2.5 bars (which is roughly 35 psi) so for a quick test I just ran all tires up to 35 and there's no errors, only a way bumpier ride. Any ideas on how to properly "reprogram" the tpms so it would accept my usual pressure without crying about it? Thank you!
My wife's CLK350 (2008) has been getting on her nerves and in turn she does on mine. The car is constantly bombarding us with any random permutation of "Please correct tire pressure", "Tire defect" etc error messages on the dash. Wheels are perfectly balanced and inflated properly, and from what I understand this is not a 'real' or active TMPS system, it just looks for fluctuations compared to the default values, I suppose somehow by looking at wheel rotation speed. I've checked my specs and this is supposed to be a "Low Line" monitoring system, no run flats or anything like that - which would mean there's no actual pressure sensors inside my tires, but I've never looked inside.
I've tried resetting the TPMS system through the dash but the errors came right back in a few minutes. Any ideas? Thank you so much!
Edit: after a bit of chatting to my tire guy it turns out I _do_ have an active sensor system, but now my main question is why the baseline values wouldn't update when I reset the TPMS. The card in the door jamb says 28 PSI front, 35 rear. I've been running this exact pressure for years, suspension is aligned to these values too. If I inflate the tires to exactly this spec the errors never stop, and when I plug in my scanner it says both front and rear axle baseline values are 2.5 bars (which is roughly 35 psi) so for a quick test I just ran all tires up to 35 and there's no errors, only a way bumpier ride. Any ideas on how to properly "reprogram" the tpms so it would accept my usual pressure without crying about it? Thank you!
Last edited by dezadam; 10-08-2023 at 12:06 PM. Reason: new infromation
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MargoSpend (10-31-2023)
10-31-2023, 09:09 PM
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My 2009 CLK has started doing this since it got cold a week or so ago.I run a lower tire pressure as it helps with ride. Even when the tires were to the “correct” PSI it still did it. When I have time to look further into this I will and hopefully come up with answers. Until then unfortunately the TPMS light stays on. If I drive 10 min it resets and goes away until car is restarted.
10-31-2023, 09:31 PM
#4
Thanks for your reply. When I got new tires they changed the tpms sensors because we thought the battery had run out. Light still stayed on after replacement. I read on a thread somewhere that it may be a bad fuse, but don’t know which one.
