I have noticed a mid-pitched humming noise in my '02. I first noticed it about a week after getting four new tires put on it. It is speed dependent, and is most noticeable at about 35 mph. Somehow I have gotten it in my head that the car might be stuck in "battery charge" mode. I can't tell easily because my car has a permanent power steering problem so I don't have the charge/power car diagram on my dash. I can still feel a difference when I shift into "B" when going downhill. I would like to check this out with my ScanguageII if possible. I see that there is a HV BATTERY CURRENT function ( HV Battery Current 8216F101D2 0316044105D2 2810 000200010000 BTA HV Battery Amps ) . Is this the charging condition, or just hte charge of the battery? Will it show the direction of amperage from battery to wheels or wheels to battery?
Have you tried pulling connector E6 so you don't have to look at the power steering warning display? Then you could see the energy flow animation. Yes, it will show you positive current when battery charge is being consumed, negative when the battery is being charged. You can also program in the xgauge for total state of charge (SOC). In normal operation the car tries to keep it near 60%. If your car were somehow stuck in battery charge, I'd expect SOC to be high all the time. You would probably also hear the battery cooling fan behind the rear seat. Whether by the xgauges or the energy flow display, you'll probably find your car is not stuck in battery charge. That just isn't a thing I've heard of happening. As the tires are the new thing, it seems tire noise would be a likely explanation. Another poster has suggested wheel bearings. If you have access to a musical instrument or tuner (or you have perfect pitch) you might try to pin down the pitch of the noise you're hearing at a few different road speeds. I now think there are a couple of pitch/road speed relationships characteristic of the front and rear wheel bearings. (The pitches given in that post are for the stock tire size; if yours are different, you can look up the revs per mile at TireRack and correct for the difference.) -Chap
Chap: By hilarous coincidence, that took me back to one of my own posts, when my PS finally gave out. Kind of neat reading my stuff from two years ago. FWIW, I stuck with my plan. Still driving the '02, still have no PS, and my next car is pre-paid. I have 160K on this one, and I'm going to see at least 200. I did check it with my scanguage, and the car isn't throwing any codes, always a good thing. I thought about bearings and the possibility that something got knocked around when the tires were changed, and I've been touching the hubs after driving to see if one was noticeably hot. No dice. I have no ear for pitch, but I might take some video/audio to see if anyone can pin it down.
But you still have a PS warning taking over your dash display? Is that with E6 unplugged? I don't get any warning shown if I unplug E6. Re: hub temperature, I have no explanation, but when my LF wheel bearing was failing that hub actually measured slightly cooler than the RF, so that didn't turn out to be a dependable test. A four-channel audio pickup was what nailed it for me. -Chap
No. I've just been living with the PS warning for a few years. It hasn't been that much of a problem until now: I might pull the E6. I haven't picked up the Toyota downloads yet, but I think I will. How accessible is the E6 once I get the glove box out?
