Aurion Stereo cuts out / Gearbox issue

[sbv16]

Hey

Just having a really strange issue with my 07 Aurion Sportivo sx6. This might sound strange but every time I drive down the road coming up to my house it is on a slight decline and as I accelerate instead of shifting into second gear it seems to always grab neutral and rev out a bit before finding gear. There is no clunk or any unusual noises when this happens. It always happens at exactly the same spot on the road. Most recently however when this is happening and I have the stereo on the music will cut out, the stereo will still be on but there will be no audible sound coming from the speakers. If I turn off the stereo nothing, it still doesnt fix the problem, however when I get home, stick the car in Park and all of a sudden music returns. At first I dismissed this as random but now Im finding it happening every night and its really starting to annoy me. The car otherwise is driving perfectly fine, no clunks, no gearbox slippage or grinding nothing. Has just knocked up 70kms.

I am wondering if this is a software issue, or ecu issue relating to the gearbox???? The confusing thing is that now the music seems to cut out randomly sometimes, and sticking it back into park doesnt always work, turning off the car and leaving it for a while sometimes does. Always happens at night time and almost always happens when the gearbox gear selector issue is present.

Dunno if anyone has had similar issues but thought I would post here and check. Car is out of warranty and taking it to a dealership and letting them rob me blind is not an option.

Cheers

Edited August 24, 2010 by sbv16

[Noodle Boy]

wow...i'm thinkin that it could be due to some interferance with the overhead power cables or something which can alter the electronics in the car. can you please explain the surronding conditions in that particular area?your situation sound sreally odd...

[sbv16]

It is a rural area with over head powerlines close to the road. The gearbox issue happens on exactly the same stretch of road, every single time without fail..... its gotten to the point now where i just dont accelerate coming down the road, I just leave it in 2nd, I think it does it going into third not second. As you would be aware the gearbox on aurions is a little bit finicky, it likes to jump gears depending on the torque / conditions, not sure exactly how it works as I have been the owner of falcons most my life. I could live with the gearbox issue, even if I do drive it normally down the road, it will rev out a bit and not select gear but eventually it finds it and off we go.

But the stereo cutting out is really giving me the ****s. I have had it cut out going down the road, then hit the next suburb, pulled over, switched the car off and it still hasnt fixed it. I have also had the stereo loose sound and have the demister on the rear windscreen knob flash.... I dunno its got me buggered. I only thought of the gearbox as an issue because they seemed to be simultaneous. But it could be unrelated. Stereo issue never occurs during the day....... only at night. Have had the car 6 mnths now and it has never done this before.

I am going to try resetting the ecu and see how that goes

[sbv16]

Ok I have now discovered both issues are completely unrelated. I reset the ecu today, has solved my gear changing issues.

Tonight whilst driving I had the stereo cut out but this time i fiddled as much as I could to find the cause of the problem. Everytime it cuts out it is when I have the heater on...... so I turned the heater off and put cool air on and sound came back on again, then to test that it was in fact related to the heating / fan i put the heater back on again and it cut out but came back on again after putting cool air on again.

So either its an overheating issue due to the heater being on, or it is related to the fan / heater in some way shape or form

[Noodle Boy]

well done on fixing the gearbox problem. the problem regarding the audio system sounds interesting to me. oh well, at least you've got that solved.

[sbv16]

Ok I have now discovered the stereo issue has nothing to do with the heater / fan.

Stereo cuts out intermittently in cold weather only. Usually at night. If I turn the volume up to medium level it cuts out, if I then turn volume down after waiting a bit the sound comes back but cuts out again when any volume increase is made. I am talking low volume here say volume level of 20 which is quite low.

I am guessing the stereo is stuffed......

[FMAN]

Before you get a new one, consider that the resistance gets lower when the temperature drops. (It is also colder at night).

If one of the speaker circuits was low resistance it would cause the output stage of the radio to overheat and then if there is a protection system it would cut out. If you turn the volume up it will get hotter quicker. This would also link to the heater warming the radio up as well.

I would check the resistance of each speaker circuit.

[mr_grumble2010]

Before you get a new one, consider that the resistance gets lower when the temperature drops. (It is also colder at night).

If one of the speaker circuits was low resistance it would cause the output stage of the radio to overheat and then if there is a protection system it would cut out. If you turn the volume up it will get hotter quicker. This would also link to the heater warming the radio up as well.

I would check the resistance of each speaker circuit.

A speaker is just a load (coil) across an output, nominally 4 ohms. There is no way that the wiring can reduce this load under any circumstance except if the two wires were shorted together creating a load of <1 ohm, which will in turn produce no sound, no matter what the volume is set to.

Drivers in low to medium end equipment don’t have short circuit protection in their final amp stages, they just stop working…….

An interesting experiment to rule the speaker / wiring theory out would be to play with the Balance and Fader to one by one move the audio output to each of the speakers, each time repeating the low volume / High volume routine and see whether this cutting out only happens when one particular output is placed under load.

My guess will be the radio that’s the culprit……

You probably have what’s known as a Dry Joint in the Printed Circuit Board, where the solder joint that electrically connects legs of components to the Printed Circuit Board is not bonded correctly. Very common and usually a bugger to troubleshoot as there can be 1000’s of these joints on a Printed Circuit Board and usually heat related, as the board gets warmer, the metals in both the tracks and solder expand, making contact again. Everything cools again, things shrink and consequently, opens the circuit again.

If this is the case, then throw away the radio and get yourself another

[GSV40R]

Hey There ,

resetting the ecu may be a short term fix. if it is still under warranty i would check with your dealer to get an updated auto ecu.There is also a procedure to add an extra 200ml of Ws auto oil as well. i had replaced mine and it fixed the shift issue 95%. from memory there was an issue found where some vehicles left the factory without the transmission feedback values entered into the ecu via the IT2 , so the toyota tech dept asks dealers to check that values have been set in the ecu. if they have and they are having flaring issues an ecu replacement will help.

now for the audio unit , i have seen a few where the lcd display just drops out and then comes back on for now reason, this is a contact issue in the unit internal plugs , simply fixed by fitting a new floater unit. i have had a couple of fujitsu units just have to sound output on radio on , cd playback is ok - yet again another internal fault (floater unit replacement).

1 customer had this same issue after a flat battery ????? who knows why ?. so replaced the unit. hope this helps