Snow Mode Coming on by Itself

Hi, my Supra is being silly and so I'm looking for help please!!

My Supra is a TT6 facelift and has the snow mode button.

For no apparent reason the snow mode keeps coming on itself and killing the power by 25% (I've read snow mode does this when activated). It doesn't matter if I'm sat with the Supra idling, going at a constant speed or accelerating hard. It will just come on itself every 1 minute or so even if I turn it off on the snow mode button.

Anyone able to shine any light on this issue please?

Thanks!! Dave

Isn't that only on autos ? I've never seen that on a manual, has it been converted from an auto ?

Nope I see tt6 facelifts had it too.

Every days a school day

in the short term is there a TRAC fuse in the main engine bay fuse box you can remove?

Short on the button/ switch/ connection from vibrations from the car? Had the dash panels out recently?? Youd be supprised how much rattling can go on in a car even though it feels smooth

Isn't that only on autos ? I've never seen that on a manual, has it been converted from an auto ?

 

Nope I see tt6 facelifts had it too.

 

Every days a school day

Yep manuals have it too

in the short term is there a TRAC fuse in the main engine bay fuse box you can remove?

That's all I could find that I could do till it's sorted.

Short on the button/ switch/ connection from vibrations from the car? Had the dash panels out recently?? Youd be supprised how much rattling can go on in a car even though it feels smooth

Dash panels haven't been off since early last year, it seems to turn off for a minute or so when I manually turn it off before coming back on again

Wasn't this a symptom of dodgy speed converter or odd way to wire in the facelifts? Can't remember now.

Wasn't this a symptom of dodgy speed converter or odd way to wire in the facelifts? Can't remember now.

I guess that's something to be looked at then thanks

I'm surprised nobody else has had this problem too

I'll agree with Pete on the possiblity of dodgy speedo converter or it's wiring, as after having searching on the interwebz I found a VVTI Supra EWD http://wilbo666.pbworks.com/w/page/57949268/2JZ-GTE%20VVTi%20JZA80%20Supra%20Engine%20Wiring#JZA80ElectricalWiringDiagramBook6742505 , (admittidly in Japanese but using the pre facelift wiring diagram for the abbreviations and circuit symbols worked out which circuit was what)

It appears the Snow warning Light Circuit runs between the Engine ECU & Speedo (as shown on the diagram) if followed up from the Engine ECU (Left Middle) SNWO Terminal to the SNOW Bulb follow that past the Fuse and along to the right of the diagram, then down to the Unit I'm assuming is the Speedometer (Gauge Symbol) as when following the other output (not earth/ ground) it leads back to the Engine ECU terminal SP1 which to me looks like Speedometer Terminal.

Only time it comes on in my triptronic is when the wheels have broken away fairly bad and then i remember to turn the TC off.

Could be a intermittently faulty ABS sensor.

I'll agree with Pete on the possiblity of dodgy speedo converter or it's wiring, as after having searching on the interwebz I found a VVTI Supra EWD http://wilbo666.pbworks.com/w/page/57949268/2JZ-GTE%20VVTi%20JZA80%20Supra%20Engine%20Wiring#JZA80ElectricalWiringDiagramBook6742505 , (admittidly in Japanese but using the pre facelift wiring diagram for the abbreviations and circuit symbols worked out which circuit was what)

 

It appears the Snow warning Light Circuit runs between the Engine ECU & Speedo (as shown on the diagram) if followed up from the Engine ECU (Left Middle) SNWO Terminal to the SNOW Bulb follow that past the Fuse and along to the right of the diagram, then down to the Unit I'm assuming is the Speedometer (Gauge Symbol) as when following the other output (not earth/ ground) it leads back to the Engine ECU terminal SP1 which to me looks like Speedometer Terminal.

 

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Cheers dude, definitely something to look at. I'll find someone to make more sense of the diagram for me but it's good you've found that

Only time it comes on in my triptronic is when the wheels have broken away fairly bad and then i remember to turn the TC off.

Same, just now it comes on regardless of moving or staying still and comes on even if I've turned the traction control off

Could be a intermittently faulty ABS sensor.

I was thinking a sensor too, it's such a pain. I just can't enjoy the car till I get it sorted.

Did you find out what is was?