1. PackratKing

    Thread Starter Well-Known Member

    Jul 13, 2008
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    My son bought a '10 Mazda 6. from square one, there has been a glitch in the tire pressure sensor system, which keeps turning on the idiot light intermittantly. He picked up a screw in a tire, and with the flat, the system worked perfectly.

    The sensors, live in the valve stem, and are rfid-type transponders, triggering based on tire pressure. Obviously some sort of peitzoelectric crystal configured as a pressure sensor. Finally after changing two valve stems/sensors to no avail, the dealer consulted Mazda Engineering..............

    Son has dribbled this car in / out of the dealer garage around 6 times now, each time the idiot light would go out before he got to the dealer, and they needed it to be on to read the computer properly.

    Lo and behold, he finally got the light to stay on, and the dealer snagged a couple codes.

    Engineering, armed with all symptoms, blamed the glitch on my sons aftermarket Pioneer GPS / Stereo / Back-up camera system, and want the factory sound system re-installed before they will go forward with troubleshooting. which to my limited knowledge of things that transmit and receive on differing bandwidths, sounds like a crock of manure. Son and I often use a set of handy-talkies between vehicles, which has no effect on the problem.

    Kick it around --- more detail forthcoming from the dealer as to what codes it threw, and any questions that may help in your diagnosis, gimme a yell.........:D
     
    Last edited: Apr 15, 2011
  2. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    This is just a long shot here but- is it possible that they use the radio receiver to decode/receive the valve cap signal then pass it along to one of the computers in the car? Doing this would save the manufacturer from adding another receiver in the car.
     
  3. retched

    AAC Fanatic!

    Dec 5, 2009
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    That would increase the cost of the radio, thus would be a loss on all of the Mazda vehicle customers who do-not pay for tire pressure monitoring.

    HOWEVER, if the back-up camera is wireless, there may be some interference.
     
  4. PackratKing

    Thread Starter Well-Known Member

    Jul 13, 2008
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    pretty sure B/U cam is hardwired, tho' I'll ask my son and post the info

    In addition, Mazda [ Ford ] knows darn well that many of their buyers are going to opt to get rid of the factory unit in favor of something better than what is offered as standard equipment, many in favor of those with the high performance amps and subwoofers.

    FCC rules [ labelled on practically every electronic device out there ] state that the device must not interfere with, and must be able to withstand interference from other devices.
    [ lousy paraphrase - point made ] ...............
     
  5. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    Having worked at Delphi/Packard Electric, all the newer cars are wired with the wiring in place for all options. If a part of the harness is not used too bad, you pay for it:p They justify it by the need to make just one wire harness instead of a special one for each option group.

    With the computer power in a modern car it would just be a software item to detect the tire monitor signal. Then it would feed out through the wire harness to the proper micro computer in the car.

    Think of all the different things in a cell phone that most people don't use.
     
  6. PackratKing

    Thread Starter Well-Known Member

    Jul 13, 2008
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    This appears to be the case........Son had the factory system re-installed, and as yet, a week down the road, the idiot light has not come on......

    I am looking at incorporating some original circuitry from the factory radio into or around his new unit, to accomodate the tire monitor, since it is likely a gov't mandated thing, and cannot be legally circumvented.

    Bells and whistles are nice, tho' I sometimes wish the Gov't would mind their own $#@}&{*% business !! :mad:
     
  7. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    I would compare the OEM radio harness to the After Market(AM) one. The AM probably use the same connector but not all of the wires that are in the OEM. Then measure the signal on those wires in the OEM harness. Then you would need to find a way to give that same signal to the idiot light wires when using the AM radio.

    The signal is probably going to be a high(+V) or low(0) when tires are correct pressure. When the AM radio is hooked up the idiot light wires were left floating and confused the computer they control.

    What brand was the after market radio? If it's one that Crutchfield http://www.crutchfield.com/app/car/carselector.aspx?lp=%2fApp%2fCar%2foutfitmycar%2fMyCar.aspx sells they may even have an adapter that will do what you need. They have all kinds of work-arounds for car audio. If not listed on the web site call the techline and talk to them :)
     
  8. whatsthatsmell

    Active Member

    Oct 9, 2009
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    I'm a little late jumping in here, but you said there was a glitch in the system from square one. Did he notice it before he had the aftermarket stereo and camera put in?

    I'd expect there is a Mazda forum online somewhere. I would post there and see if anyone else has experienced this problem. And usually there are some pretty smart people in the industry that monitor the forum (just like here ;)) and may be able to help.
     
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