FEH/4WD/Scanguage-II
#121
10-05-2009, 07:03 PM
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Re: FEH/4WD/Scanguage-II
Yes, I believe that TC using the ABS is only below 62MPH. ABS pulses all the wheels, TC pulses selective wheels.
At one time there were 3 channel and 4 channel ABS's. With a RWD 3 channel system if either rear wheel started to lock due to braking BOTH were "unbraked".
4 channel ABS have the ability to "unbrake" ANY wheel or wheels. I think most modern day Anti-lock Braking systems are all four channel.
Due to a small matter of physics most ABS unbraking activity occurs at the front wheels
TC first "appeared" only for the primary drive wheels, the rear wheels, RWD, or front wheels, FWD, as it was thought that full-time AWD (automatic PART-TIME 4WD) would suffice. These days I don't know of any TC system that does not have the ability to brake any one wheel individually, or multiple wheels (up to 3..??) if that is what is required. Most have some form of LSD using TC as the "engine".
The Toyota HL & Sienna, and the Lexus RX, for instance, even extend the LSD simulation aspect to otherwise fully "open" center diff'l.
I would/will place my bet that TC does NOT use wheel braking above 25MPH. Seems to me that might be somewhat dangerous, differential braking at speeds higher than that.
That's a form of full time 4WD not AWD that applies traction to the rear wheels when the front tires lose traction.
AWD can send torque to one single wheel by using TC which uses the ABS system to pulse the brakes on three wheels.
The FEH didn't have TC till '09 therefore, it couldn't be labled as AWD.
TC, literally or absolutely technically, REQUIRES dual mode, dual electrical actuation solenoids, for each wheel wherein TC is to be "imposed." Many earlier F/awd and R/awd systems (early FE and later FE/FEH included) (automatic PART-TIME 4WD systems) did not have TC.
They simply had some method of engaging the opposite drive set if wheelspin/slip was detected at the primary set.
TC is a modified ABS program. There is also a trailer ant-sway program built into the TC system which can be turned OFF.
At one time there were 3 channel and 4 channel ABS's. With a RWD 3 channel system if either rear wheel started to lock due to braking BOTH were "unbraked".
4 channel ABS have the ability to "unbrake" ANY wheel or wheels. I think most modern day Anti-lock Braking systems are all four channel.
Due to a small matter of physics most ABS unbraking activity occurs at the front wheels
TC first "appeared" only for the primary drive wheels, the rear wheels, RWD, or front wheels, FWD, as it was thought that full-time AWD (automatic PART-TIME 4WD) would suffice. These days I don't know of any TC system that does not have the ability to brake any one wheel individually, or multiple wheels (up to 3..??) if that is what is required. Most have some form of LSD using TC as the "engine".
The Toyota HL & Sienna, and the Lexus RX, for instance, even extend the LSD simulation aspect to otherwise fully "open" center diff'l.
I would/will place my bet that TC does NOT use wheel braking above 25MPH. Seems to me that might be somewhat dangerous, differential braking at speeds higher than that.
That's a form of full time 4WD not AWD that applies traction to the rear wheels when the front tires lose traction.
AWD can send torque to one single wheel by using TC which uses the ABS system to pulse the brakes on three wheels.
The FEH didn't have TC till '09 therefore, it couldn't be labled as AWD.
TC, literally or absolutely technically, REQUIRES dual mode, dual electrical actuation solenoids, for each wheel wherein TC is to be "imposed." Many earlier F/awd and R/awd systems (early FE and later FE/FEH included) (automatic PART-TIME 4WD systems) did not have TC.
They simply had some method of engaging the opposite drive set if wheelspin/slip was detected at the primary set.
TC is a modified ABS program. There is also a trailer ant-sway program built into the TC system which can be turned OFF.
#122
10-05-2009, 09:40 PM
Re: FEH/4WD/Scanguage-II
Yeah, the ATC is 12V but in machines I speak of it wasn't 300-600V but just 90-110V.
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