2007 ES 350 Speedometer Error
07-07-07, 12:24 PM
#1
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2007 ES 350 Speedometer Error
I have noticed that when I go passed one of those unmanned radar units that my speedometer is not reading what the radar says. This happened once at 25 mph indicated on the car…the radar read 23. Then again on the freeway the speedometer read 70 and the radar indicated 68. I checked with my local dealer and he said this is common to all Lexus models (liability Issues is what I was told.) I do not know when this policy started but I believe it was after 2003 since I had a 2003 ES300 and do not recall this problem.
Q. Has anyone else experienced this?
Q. Is there a fix for this? My Lexus dealer says “no”
It is not a big deal, I suppose, except in order to drive 35 I have to indicate 37 on my speedometer so I can keep other drivers from piling up on my bumper
, which is what made me suspicious to begin with. It is just a bit annoying.
Q. Has anyone else experienced this?
Q. Is there a fix for this? My Lexus dealer says “no”
It is not a big deal, I suppose, except in order to drive 35 I have to indicate 37 on my speedometer so I can keep other drivers from piling up on my bumper
, which is what made me suspicious to begin with. It is just a bit annoying.
Last edited by bobbert; 07-07-07 at 12:33 PM. Reason: update information
07-07-07, 04:34 PM
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Is there a digital speedometer that I don't know about? The graduations on my speedometer are so fine, I am not sure I could tell the difference between 23 and 25.
It would be a nice feature for the NAV
It would be a nice feature for the NAV
07-07-07, 08:04 PM
#5
Unfortunately, speedo calibration is not an exact science. It is generally done by defining a set tire circumference (or diamater, or revs per mile...essentially the same thing) into the engine's ECU (or PCM...pick your acronym).
The part that isn't exact? Your tires. They're taller or shorter based on either sidewall compression or amount of tread. The former...inflation pressure and payload both play a role. The latter...simply how many miles you have on the tires. Even brand new tires of the same size from different manufacturers will generally differ in circumference.
All of that is on the vehicle end. There's no guarantee the radar detector is calibrated correctly. Bottom line...as long as you're within a few mph I wouldn't sweat it, or certainly wonder if there's something wrong with your car.
The part that isn't exact? Your tires. They're taller or shorter based on either sidewall compression or amount of tread. The former...inflation pressure and payload both play a role. The latter...simply how many miles you have on the tires. Even brand new tires of the same size from different manufacturers will generally differ in circumference.
All of that is on the vehicle end. There's no guarantee the radar detector is calibrated correctly. Bottom line...as long as you're within a few mph I wouldn't sweat it, or certainly wonder if there's something wrong with your car.
07-07-07, 11:45 PM
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A portable handheld GPS system (like a Garmin Trex) will be able to accurately measure the speed of you car. Too bad the ES 350 nav doesn't have real time speed readings.
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07-08-07, 09:45 PM
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at least there is a two mile difference than what the cop that has pulled you over thinks you were driving. complicated sentence gramatically. lol i had to rewrite this 2 times. 
07-09-07, 10:07 AM
#11
I have also notice that if I drive 60 MPH (or whatever) consistently for a while after resetting my Average Mile Per Hour (on the digital display panel), it will always read about 2 mph differnt than what the analog speedometer reads. I would at least like them to be the same, if it won't match the radar.
07-09-07, 06:00 PM
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That’s got to be wrong!!!
07-10-07, 09:22 AM
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FWIW – maybe this can be of interest to others riding on 20’s. After posting my above post I noticed that my 20’s are just a little larger in circumference than the stock tires. Well there you are my tires are turning at a slower rate of speed than others running on the stock tires. That would explain why my car shows the correct speed in the Speedo. Probable if I had the stock tires on my car the Speedo would show 2 MPH over actual speed too.
Last edited by osokuko; 07-10-07 at 09:25 AM.
07-12-07, 08:17 AM
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All car companies do this. It's partly to save your *** from a possible speeding ticket. The higher the speed, the higher the difference. BMWs are really bad about this. A friend was driving his M3 past one of those speed guns on a highway going 90 as indicated by the speedometer but the speed sign showed 83.
