ASR defeat switch thread

[mrem]

Has anyone had any experience with the ASR defeat switch advertised by "Precision Auto Designs" for $475.00. This is considerably less expensive than Renntech's switch. I'm considering it for my E500.

[David Hendy]

I have one on my 500E, works great. Fantastic for the track, with larger rear rims/tires it is essential.

David Hendy
'92 500E

[ricardo]

David

Where did you get your ASR defeat switch? Is it to complicated to install? Is its recommended for street use?

I do have a larger rear rims/tires on my 1992, 500E and I’m wondering (after following these post) if a ASR defeat switch would appealing for regular street /high way driving, not necessary race track.

What is your opinion?


Ricardo

[rainmaker]

Since you already have staggered wheels/tires, you might want to try a first gear start mod first, which, as the name implies, allows you to start in first gear for better launches. The wider rear tires would be important to try to keep the rear tires planted and thus, together with judicious application of the right foot, would keep ASR from engaging. The next logical step would then be the ASR defeat.

I think those three go together...wider rear tires, 1st gear start and ASR defeat...

You might want to try a search for '1st gear start' and 'Satish Tummala' who can supply you these...

Hope that helps.

[David Hendy]

Well, I would say an ASR switch would be more useful than a 1st gear start.

Firstly you can get around the first gear, by using the shifter, inconvenient, but not impossible. You cannot do this with ASR.

Secondly with ASR switched off the car is easier to drive (if you know what you are doing) because ASR does not intervene, wet weather driving is much more predictable.

Lastly on dry pavement, the ASR switch allows full use of all the horsepower. The larger rear tires allow you to put the hp to the ground and the ASR switch allows some wheelspin to make sure the engine spins into its high torque area.

It just lets you drive the car not the car drive you.


David Hendy
'92 500E

[rainmaker]

I forgot to add...

The first gear start kit also allows you to engage first gear without having to engage the kickdown button which entails pushing the gas pedal all the way through. Makes the car a bit more responsive, without that annoying lag.

In my experience though, the wider rear tires take care of keeping ASR from engaging all that often, although if you launch hard enough you will still engage ASR.

I guess it would depend what you're trying to achieve.

In the end, it would be optimal to have all three (including wider rear tires).

Cheers!

[ke6dcj]

You don't have to engage the kick-down switch to have 1st gear start.

When stopped, shift all the way down to "2", then over to the right "B2", and then bring it back to "D" or "3".

Press firmly down on the accelerator (no need to engage the kick-down switch), and you will start in 1st gear.

I've studied the ASR defeat switch & the ASR ciruit, and will have a prototype for testing soon. It will be significantly cheaper than the $475 design.

:-) neil

[rainmaker]

True dat, Neil...

...but only from a stop.


Keep us posted on your ASR defeat...

[ricardo]

Rainmaker

My 500E comes with transmission mode shift selector. This switch is specific to many European models (My case); I don’t think it is found on the North American 500E’s (????).

The transmission mode shift selector to my understanding, allows when place in standard position, to start out in 1st gear when accelerating briskly and electronically shift through the proper gear sequence.

Please check http://www.mbcoupes.com/specialequipment/shiftselector.htm

Would these transmission mode shift selector replace the first gear start mod?

Thanks!!

Ricardo

[rainmaker]

Ricardo,

The other MBs I have and have had are all Euro spec *except* for the 500E and the SL500. I noticed though that the switch holds the shifts longer but I am not sure how it works with the 500E. The cars I've driven with the S/E switch have smaller engines and normally start on 1st gear if I recall correctly.

You are correct, the S/E switches are not supplied with North American spec E500/500Es.

From what is stated in the link you posted, it would seem that you don't need 1st gear start, lucky you.

Send us some pics!

[ke6dcj]

Ricardo- you are very lucky. You get decide when to have a 1st gear start or a 2nd gear start.

The switch is also known as a "Summer/Winter" selector.

If you could be so kind and post the Mercedes part numbers (schematic too!) for this you would make a lot of 500E/E500 owners very happy.

:-) neil

PS: do Euro-spec 500E's come with an ASR defeat switch?

[ricardo]

Rainmaker

Thank you for your replay and your comments!!

I will send you some Pictures next weak, including The transmission mode shift selector and a very rare special equipment that came with my 500E, call the Trip computer; In that you can program the distance and time to destination and it keeps you informed as to when you will arrive, mileage (in km), fuel consumption (in liters/100 km), time and average speed. I though you might be interested to learn about these very rare special equipment.


Neil

I’m going to check with my local MB service shop about the parts numbers, I assume that Parts are available, but I don't think there is a complete kit for aftermarket installing. One may have to buy every part extra. I will try to get the information!!

In regard to your question do Euro-spec 500E's come with an ASR defeat switch? I believe mine does not has the defeat switch. But it is a good question. I have to ask my MB service shop. I don’t promise a fast response on that!! You know, in my country the MB dealer was allowed to order only two 500E back in 1992. So, the 500E is a rare animal even for the MB engineers at the service shop.

Thanks

Ricardo

[ricardo]

I’m not too knowledgeable when it comes to technical maters, but for what I understood from a German Mercedes Benz technician. The switch that has a wheel with a chain -for snow-on the 500E/E500 console (next to the hazard lights switch, above the air conditioning control) is technically an ASR defeat swch. It does defeat the ASR system.

Could that be possible?

[Michael]

Ricardo,

No, the "snow chain" switch simply allows a little more speed differential between the front & rear wheels, thereby allowing a little more "slip" than in standard configuration.

Senior Hendy,

All good points you've made, but you are a highly trained Pilota (or in Italian is it "Pilote"?). Somebody like me in the rain, with ASR defeat, would likely loop the vehicle and kill both the vehicle & themselves.

If you aren't used to high-power vehicles, don't do the ASR defeat switch unless you know EXACTLY what you're getting into. David can absolutely deal with it, and I'm sure Alain, Dean, Tackman and a few others would be fine, but I know ASR has saved my hiney a few times...

[David Hendy]

Curcio

As you and I have discussed before, it is not ASR itself that causes the problem in the wet. However, there is a slight delay between the time that, say, the rear of the car steps out and ASR kicks in.

I know for a fact that I will "steer in" to the skid in that delay time and all of sudden, ASR says "nein" and we have no more power. Then you find yourself pointing in the wrong direction with no gas. So, unless you can turn off the instinctive reaction of steering into a skid, ASR is not for you. However, if you let the car do its thing, then it will save your arse no doubt.

Then a see saw situation develops with the rear going from one side to another ASR on and off.

No thank you.

The track situation is another no no for ASR.



David Hendy
500E '92 68k miles