mattylex77

My speedometer reads 3 mph slower than the car at all speeds.

every time i pass a "your speed" radar thing on the roadside it says I'm going 3 mph faster than my speedo says, initially this is how i noticed it.
today i had the inspiration to reset my average speed while driving at what my speedo said was 35 exactly for an extended period and sure enough the average speed was 38, NOT 35.

So the computer knows the actual speed of the car but the speedo doesn't, its ALWAYS 3 mph slower. I do have to smack the dash in warm weather to get the tach and speedo to unstick.

side note: the lights in the trans selector don't always come on unless i smack the shifter from D to 4, then they come on and stay on, also the PWR/ETC switch is never illuminated not sure what its supposed to do there.

Also the lock/unlock switch on drivers side panel doesn't work at all.
i could be looking at an electrical issue coming from one source, maybe its all related???

RA40

iTrader: (6)

What year Lexus? What size tires-wheels on the car? The lights and switch would not be related. Spilling liquids in the gear selector area is a problem. The door switch is worn and two things to try, cleaning the contacts and or replacing it. (I'm presuming that the passenger side lock switch will work the lock actuators.)

billydpowe

iTrader: (1)

yes, it always helps to identify your car for us

paulo57509

The speedometer in my '98 is inaccurate as well (reads faster than actual road speed). I'm running stock size tires, etc.

I set the cruise at an indicated 60mph and it takes a little more than 60 seconds to travel 1 mile (using the roadside mile markers....not the odometer). Indicated 60mph vs. time calculates out to about 57mph.

I'm sure it falls within the plus/minus acceptable error or what ever Toyota or the regulating body for this kind of stuff specifies. Yet it bugs me as well.

I also don't think the inaccuracy is linear across all speeds.

So we're back to your question as to how to correct for the inaccuracy?

mattylex77

thought you guys would have picked up on the D to 4 thing, its a 99. Im running 430 17's but the overall tire diameter is the same as the 16's, just a lower profile tire.

Neither door switch works and the remote sometimes can't lock the door. its worse when I've been in stop and go traffic with AC on and then park and try to lock the car.