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DTC light

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3.6K views 19 replies 8 participants last post by  benjamin84  
#1 ·
Guys,

Tell me something, is DTC on when the light is on? or off?

im confused!
 
#2 ·
When the DTC light is on that means its on, when there is no lights on that means Normal traction control is on and when you get the icon with the exclamation mark with the circle around it that means everything is off.

Grant
 
#5 ·
I think it's ON by default ... when you push the button it is turned OFF hence the warning light on the dash?

If you think about it, that's the logical way to do it.
 
#7 ·
This has been covered SO many times, but here it is again.

Get in, turn engine on, no lights, this means you have DSC.
DSC will apply individual brakes at each corner, and/or pull power very quickly.

Press the DTC button on the dash briefly: you have now turned DSC off and turned DTC on.
DTC will allow some "play" before using the brakes and/or pulling power.
This is great for pulling away on loose surfaces where occasionally you need to allow a little slip.
It's also good for trying to slide the back end round roundabouts because you'll only get so far before the DTC collects it for you.

Press and hold the DTC button and you have no DSC and no DTC, just ABS. Now if you get it wrong whilst on the power, the computer(s) will not save you...
 
#12 ·
The manual covers this...

My advice turn the traction control OFF and leave stability on for snow. To me the Traction control seems a little on the intrusive side...
 
#13 ·
corgi said:
The manual covers this...

My advice turn the traction control OFF and leave stability on for snow. To me the Traction control seems a little on the intrusive side...
You can't do that though, DSC (stability) is default, pressing the button momentarily turns off DSC but leaves DTC (traction control) on. The traction control activated when DSC is off is less intrusive though, lets the wheels slip/spin a bit more before cutting in.
 
#15 ·
Locoblade said:
You can't do that though, DSC (stability) is default, pressing the button momentarily turns off DSC but leaves DTC (traction control) on. The traction control activated when DSC is off is less intrusive though, lets the wheels slip/spin a bit more before cutting in.
From my experience this is what happens:
DSC (default): Both stability and traction control on
DTC (one press): Stability on, traction off. If you keep the car straight you can spin the rears as much as you want, if it goes sideways past a certain point the stability control will step in.
Off (long press): You're on your own ;) Sadly not ideal for snow as it will let one rear wheel spin uncontrollably which compromises traction.

My conclusion is that DTC is the best on snow, it will stop one-wheel-spin, acting like a primitive limited slip diff, and will allow you to slide around a little without cutting engine power.
 
#16 ·
verysideways said:
felsteaduk said:
So which is best for snow / icy roads?

DSC
DTC
NONE !!!
One quick press of the DTC button - this will give you a little slip but not lots.

Ultimately if you get lots of wheelspin in snow you've messed up already :)
Exactly as I understood it from reading the manual, one quick press of the DTC button turns the traction control off and leaves the stability control engaged. A little slip in snow is useful...
 
#17 ·
benjamin84 said:
Locoblade said:
You can't do that though, DSC (stability) is default, pressing the button momentarily turns off DSC but leaves DTC (traction control) on. The traction control activated when DSC is off is less intrusive though, lets the wheels slip/spin a bit more before cutting in.
From my experience this is what happens:
DSC (default): Both stability and traction control on
DTC (one press): Stability on, traction off. If you keep the car straight you can spin the rears as much as you want, if it goes sideways past a certain point the stability control will step in.
Off (long press): You're on your own ;) Sadly not ideal for snow as it will let one rear wheel spin uncontrollably which compromises traction.

My conclusion is that DTC is the best on snow, it will stop one-wheel-spin, acting like a primitive limited slip diff, and will allow you to slide around a little without cutting engine power.
You could be right, thats not how I understood it though and not how Verysideways has explained it earlier in the thread. I always thought that DSC is switched off (or toned down) with a push of the button which means it doesn't intervene so enthusiastically, which in turn means the first thing to reign you in is the traction control rather than the stability control.

One way to test would be to press the button quickly then try a fast standing start in the wet. If you're correct you should get rampant wheelspin because the car will be straight so DSC won't be having a panic, and DTC will be off. I think though you'll find traction control still kicks in.

Will give it a go tomorrow if it's wet and I can find a suitably quiet bit of private road.
 
#18 ·
If you read the manual:

1. DSC is the default setting.

2. When you do a quick press of the DTC button you are turning Dynamic Stability Control OFF and turning Dynamic Traction Control ON.

3. If you press and hold the button for 10 seconds you are turning both DTC/DSC OFF.

DSC is all consuming
DTC will let you do a little slippy slidey
Both off will let you crash the car if you want to :)
 
#19 ·
verysideways said:
If you read the manual:

1. DSC is the default setting.

2. When you do a quick press of the DTC button you are turning Dynamic Stability Control OFF and turning Dynamic Traction Control ON.

3. If you press and hold the button for 10 seconds you are turning both DTC/DSC OFF.

DSC is all consuming
DTC will let you do a little slippy slidey
Both off will let you crash the car if you want to :)
You are right, the problem is the names are somewhat misleading. What Dynamic Traction Control actually does is what I described above, it will allow wheel spin as long as it doesn't think you are "out of control", in other words it will step in only when things get too sideways.

If you think about it, the opposite would be rather dangerous. Full traction control preventing any wheel-spin, but if you overcook it through a corner there is no stability control to save you, and you are also not allowed to correct your trajectory with the throttle due to the traction control stepping in.

So in summary:
Dynamic Stability Control: No wheel-spin, no slip
Dynamic Traction Control: Full wheel spin, some slip. Too much slip = intervention almost as if DSC was on.
Off: You're on your own ;)
 
#20 ·
Locoblade said:
You could be right, thats not how I understood it though and not how Verysideways has explained it earlier in the thread. I always thought that DSC is switched off (or toned down) with a push of the button which means it doesn't intervene so enthusiastically, which in turn means the first thing to reign you in is the traction control rather than the stability control.

One way to test would be to press the button quickly then try a fast standing start in the wet. If you're correct you should get rampant wheelspin because the car will be straight so DSC won't be having a panic, and DTC will be off. I think though you'll find traction control still kicks in.

Will give it a go tomorrow if it's wet and I can find a suitably quiet bit of private road.
I have tried this quite extensively on snow. Wheel spin is allowed, but with two conditions:

:idea: Both wheels must be spinning, if only one spins it will try to slow this down using the brakes, like a crude limited slip diff. (Edit: There might be a limit to how much wheel spin is allowed, not entirely sure, but that limit is pretty high ;) )
:idea: You must be going straight! The car allows a bit of sideways motion, but once you exceed this it will (most often) start applying the brakes to the appropriate FRONT wheel to snap the car back into line. This is very much a Stability Control function, rather than Traction control related.

An example: In a snowy roundabout in DTC mode, if I manage to keep the angle of slip relatively small, I can keep the rear tires spinning all the way around. However, the moment the slide gets too wide, the car will straighten me right back up (sometimes quite brutally) by applying the front brakes (outside front I think, might be wrong).

I must admit though, I've got no experience with how this works on wet tarmac (well, except that if you turn it all off you will indeed be allowed to head off into the scenery... :redface: ) so it might take much more provocation to get the Stability Control to intervene. I recommend that in addition to trying a full-bore standing start, you also try to initiate a powerslide and see how the car reacts, I am pretty sure it will allow enough wheel-spin for you to get sideways, but will then straighten you up once the slide gets too wide.