I don't know. someone help me out here please

 

TCS = garbage

It only apply front brake to reduce the wheel spin. Won't work above 25 mph. It will not correct over/understeer for you.

VSA will apply front left/right brake individually to correct under/oversteer for you. works at all speed. Of course it will do what the TCS can do as well. I am not sure if the VSA got fuel cut off or not..

 

Wellll...

I think this has been covered before and should go into the FAQ.

TCS: Applies one or both front brakes to arrest wheel spin below 18MPH. Helps during acceleration on low-traction surfaces, but no help when cruising.

VSA: Applies one or both front brakes and reduces throttle to control wheel spin at all speeds. Also has a yaw sensor to monitor how rapidly the car is turning compared to the steering input. In case of an oversteer or understeer, applies one front brake and optionally reduces throttle to keep car on the intended turning path.

 

TCS (Traction Control System) only only works with your front wheels. It uses the ABS sensors to determine if one of your front wheels is slipping. The way most systems work is that when wheel slippage is detected, TCS will apply slight braking pressure to the slipping wheel in order to obtain traction. Some systems even tap into the engine management system (retarding spark or cutting fuel) to bring down RPMs to help. I know the system in the TL uses braking, but unsure about engine management.

VSA (Vehicle Stability Assist) does everything that TCS does, but also uses a Yaw sensor that determines the car's angle, compares it with vehicle speed, rotation speed of each tire and steering position to evaluate whether or not the car is in a skid. If it determines that the car is in a skid, it can individually apply the brake(s) to a single, two, three or all wheels to try and pull the car out of a skid. Like ABS though, it cannot defy the laws of physics. If you enter a 20mph hairpin turn doing 90mph, your going to be toast, regardless of what is trying to help you.

Lastly, since VSA needs individual control of each tire, the TL-S has four channel ABS vs. three channel for the TL. The three channel system on the TL means that the rear wheels are on one channel, so if there's impending lock-up on either of the rear wheels, the ABS ends up pumping both of the rear wheels. Not really a big deal since the front brakes do most of your stopping.

Hope this helps.

 

Thanks for the info.

greatly appreciated

 

Actually, this is only partly correct. The ABS on the TL-S works as a 3-channel system under normal driving conditions (rear wheels modulate together regardless of slip/lockup). Only when the VSA detects impending trouble and activates does the rear channel split to operate both wheels independently. So I guess you'd call it 3.5-channel...

 

The ABS on the TL-S works as a 3-channel system under normal driving conditions (rear wheels modulate together regardless of slip/lockup). Only when the VSA detects impending trouble and activates does the rear channel split to operate both wheels independently. So I guess you'd call it 3.5-channel

Thanks for the note and clarification. I knew that 4-channel ABS was required for individual wheel modulation, I just wasn't sure if individual rear-wheel modulation occured in a typical braking event where one of the rear wheels was going to lock-up.

Thanks again.

 

Yet I didn't know what as well... How do you know those stuff? Just wondering cuz I want to know stuff like this as well......

 

Yet I didn't know what as well... How do you know those stuff? Just wondering cuz I want to know stuff like this as well......

As for me, I'm just a car geek. I subscribe to Motor Trend along with Car & Driver and also spend way too much time on websites such as this.

I'm filled with useless trivia on cars. I drive my wife nuts. We'll be watching TV and there'll be a shot of two people driving along in a car. All you can see are the headrests or maybe part of the dash or steering wheel. I immediately tell her what car it is (like she really cares), and I almost always get it right, if I miss it I usually have the manufacturer right.

She calls me the "rain man of cars". I also practically grew up in my uncle's auto repair shop.

 

Sorry, but you're mistaken. VSA operates the brakes only only on the front wheels, plus controls throttle. Check out Acura's description.

Again, TCS does not control throttle, only applies brakes. Read Acura's description.

The ABS system on the TLS is indeed a "3.5" channel model. It normally brakes the rear wheels together. However, if the yaw sensor detects that the car is in a significantly severe turn, the ABS system will apply more brakes to the outside rear wheel than the inside one. This is an ABS feature, not VSA. The difference? ABS works when you're braking, VSA works when you're accelerating.

 

Daverman you are correct. I re-read my post and realized it was incorrect. I used the wrong acronym--VSA instead of ABS.

 

Sorry, but you're mistaken. VSA operates the brakes only only on the front wheels, plus controls throttle. Check out Acura's description.

I stand corrected. I should have known to check out the Acura site.

Based on what has been shared, The Acura VSA is not the full blown stability control system found in some of the higher end cars. I recall reading that these systems could apply braking pressure to an individual wheel to bring a car back to it's intended course.

 

Daverman,

You're incorrect. This is from the Acura Press Kit:

"The TL's standard 4-wheel Antilock Braking System (ABS) enhances steering control during hard braking. Speed sensors at each wheel send signals to the ABS control module. When the system detects impending wheel lockup, it first holds, then reduces hydraulic pressure to the affected wheel, letting it regain traction before full braking resumes. The ABS function is also highly effective on split-friction surfaces, in which one side of the vehicle has significantly less traction than the other.

The Type S is fitted with a special four-channel system that works in conjunction with the VSA system. The ABS systems operates in three-channel mode during straight-line braking, apportioning braking power to the front wheels independently and the rear wheels in tandem. This enhances the driver's ability to maintain steering control during panic stops on slick road surfaces.

The system automatically switches to a four-channel mode when the system senses high cornering forces. This allows the ABS system to take advantage of weight transfer to the outside of the turn during cornering and apply higher brake pressure to the outer rear wheel for enhanced braking performance."

 

I'll come to Daverman's defense (not that he needs it ) and say that his original statement is correct. What you are reading applies to the *ABS* system. Although Daverman spoke of both ABS and VSA, he correctly stated that the *VSA* system can only operate the brakes on the front wheels. I confirmed this by a diligent review of the 120+ pages related to the VSA system in the 2002 Helms Factory Service Manual.

Think of it like this: If you were accelerating rapidly to 70 mph around a wet right-hand spiral on-ramp to a highway, as the speed increased the car would have a tendancy to understeer (plow straight ahead due to lack of traction). The VSA would then kick in and modulate the right-front tire (inner tire in this example), which would create drag on the right side of the car and "help" the car turn more to the right. If modulating the brake doesn't work, it can also cut the throttle to help get the car in line. VSA works for acceleration-related handling issues.

Now the converse: If you were braking and decelerating rapidly from 70 mph around a wet right-hand spiral off-ramp from a highway, as the speed decreased the car would have a tendency to oversteer (rear end come around past the front due to lack of traction in the rear). The ABS system would most-likely already be activated (because of the wet) and it would detect the high-cornering force (off-ramp) and switch to 4-channel mode and would modulate the outside rear wheel independant of the inside rear wheel because the outside wheel has more weight [downforce] on it=better traction. This is the ABS doing this, not the VSA. ABS works for deceleration-related handling issues (provided you are using the brakes).

So Daverman is correct, VSA can only work the front wheels, although it does have sensors at all four wheels so it can keep track of what's going on and make its adjustments accordingly. Acura's press kit talks about the ABS working in conjunction with the VSA--it does only to the extent that it controls the ABS functions on the front wheels as necessary.

 

Yeah, what Matt said.