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Discussion Starter #1
I got this idea from the thread Servotronic SUCKS.

So I went ahead and disabled the Servotronic steering. With Powerchip, the throttle map in Sport Mode was too steep for my liking, but I did prefer the (slightly) heavier steering that Sport Mode provided. But I always more, more, more (effort).

But now.... after disconnecting Servotronic... WOW. It requires MUCH more steering effort at low speed. Much more effort that Sport Mode ever would provide. I'm not sure if I even like it - I'll have to log some more miles on it to be sure. My car did not throw any codes (no SES light) with this "mod".

This is a fast mod that is easily undone if you don't like it. But the long-term effects are unknown - so there is some risk, I suppose.It's a 15 minute job, tops. All I did was remove front left wheel, pop open the door on the connector box, and pull apart the white connector. Taped it up using electrical tape to keep dirt and corrosion away. I put the long part of the white connector back inside the junction box, and tucked the short white end (taped also) up under the plastic inside fender.


Again - use at your own risk - the ill-effects are unknown!





If anyone wants to try this, please post your impressions.

:cheers:
 

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ELEVENS said:
I got this idea from the thread Servotronic SUCKS.

So I went ahead and disabled the Servotronic steering. With Powerchip, the throttle map in Sport Mode was too steep for my liking, but I did prefer the (slightly) heavier steering that Sport Mode provided. But I always more, more, more (effort).

But now.... after disconnecting Servotronic... WOW. It requires MUCH more steering effort at low speed. Much more effort that Sport Mode ever would provide. I'm not sure if I even like it - I'll have to log some more miles on it to be sure. My car did not throw any codes (no SES light) with this "mod".

This is a fast mod that is easily undone if you don't like it. But the long-term effects are unknown - so there is some risk, I suppose.It's a 15 minute job, tops. All I did was remove front left wheel, pop open the door on the connector box, and pull apart the white connector. Taped it up using electrical tape to keep dirt and corrosion away. I put the long part of the white connector back inside the junction box, and tucked the short white end (taped also) up under the plastic inside fender.


Again - use at your own risk - the ill-effects are unknown!





If anyone wants to try this, please post your impressions.

:cheers:
Other than minor bicep buildup :D I don't think there will be any long term ill effects. This has been going on with the some the early 90's Audi's; same complaint, same fix, no bad results. The only issue is whether or not the lack of assist is too detrimental at low/parking speeds. That is an indivdual decision.
If you wanted to be real trick, you could try to run a wire up to the cabin and put an on/off toggle switch on it. Then, with Servotronic connected at the wheel, you should be able to turn it on or off from the cabin!
Regards,
Jerry
 

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gsfent said:
Other than minor bicep buildup :D I don't think there will be any long term ill effects. This has been going on with the some the early 90's Audi's; same complaint, same fix, no bad results. The only issue is whether or not the lack of assist is too detrimental at low/parking speeds. That is an indivdual decision.
If you wanted to be real trick, you could try to run a wire up to the cabin and put an on/off toggle switch on it. Then, with Servotronic connected at the wheel, you should be able to turn it on or off from the cabin!
Regards,
Jerry
That is an outstanding idea...anyone have any good ideas for an OEM button to use?

I want to do this mod this week!!!

Servotronic SUCKS (except when parking).

R
 

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My only guess at a possible negative, is premature wear of the splines between the steering wheel and hub. Based on my experience replacing my prior cars' steering wheels with momo steering wheels, the hub was different for power steering cars and non-power steering cars (with the splines being much deeper on the non-power steering). Again, this is just a guess, but may be worth considering. I'm sure there are several other parts that were designed with power assist in mind.
 

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Excellent work, Elevens!

I assume it is a wheels speed sensor you have disconnected, and that it is not connected to the ABS system.

Have you checked if the sensor is connected to anything else, for example the speed-dependent radio volume control, and the nav system?

Best Regs,

David
 

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Discussion Starter #6
DavidS: The disconnected cable connects directly to a small module on the steering box, so it would seem that we are addressing the "problem" directly at the source.

Ag Surfer: Power steering isn't lost, just the speed-sensitive "Servotronic" feature.

gsfent: Good and very interesting idea about the cabin-mounted switch. It's possible it won't be needed though, it's not that much harder to turn, just heavy enough to be very noticable. Folks shouldn't be scrubbing (turning) the wheels when the car is not moving, anyway.

Like you said - individual decision (for the switch). Let us know if you find an OEM switch that'll look good.



cherrsagai
 

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ELEVENS said:
DavidS: .

Like you said - individual decision (for the switch). Let us know if you find an OEM switch that'll look good.



cherrsagai
If the switch for the tire defect system would work, why not another one, on the drivers side, so it is symmetrical and no one will know it is there? Or, how about one of the switches in the center console ( PDC, Sport button, DSC) and add a switch there..It would also look like factory.
Regards,
Jerry
 
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WOW! I hadn't noticed this thread.

GREAT work, Elevens!! Now I'm tempted to try too!

Can you tell us a bit more about the feel? How would you compare it in terms of consistency and weighting to the regular series (non-servotronic) BMWs with the heavier steering?
 

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Discussion Starter #9
Opposite_Lock said:
WOW! I hadn't noticed this thread.

GREAT work, Elevens!! Now I'm tempted to try too!

Can you tell us a bit more about the feel? How would you compare it in terms of consistency and weighting to the regular series (non-servotronic) BMWs with the heavier steering?
I reconnected it after a couple days. It was just too much effort to turn in the parking lots for a daily driver. But the feel when moving was fantastic!!!
 

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I believe the servotronic unit is a 10 ohm coil or similar that requires a varying, modest current source to alter steering effort.

If somebody can temporarily bridge voltmeter across this 2 wire ckt and plot the voltage curve wrt speed, we might figure out what's going on.
 

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I'll likey do it at or near the time I switch the car to 275's all around. This will serve as good reminder to not play with the steering when the car is not moving. Increase the lifespan of my (soon) x5 bushings and steering box. (which the hoses need re-clamping).

LSCman: Me tech! is that a 10 ohm resistance 'resistor', or a 10 ohm resistance 'coil' or 'inductor'? It sounds like a proper passive circuit. I like KISS design. Less likely to break.

I'm thinking of getting a scope-meter with PC hookup, which is what I expect you'd like to see. a voltage-over-time chart.
 

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Back from the dead!

:)

So...anyone has pics of this procedure? I'm really interested in trying this on my 2K S2 M5. Maybe even put together a potentiometer that can increase/reduce steering effort from inside the car. Can't be that complicated if it's just voltage. Already have GC coilovers, monoballs and 275 PS2 up front, so this should help nicely.

A
 

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Took my wheel off today to do this...here's a photo. What do I unplug here? I see a bunch of wires.

 

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So does this completely disable power steering? I took the P/S out of my Integra but can't imagine it with a heavier car with much wider tires!

I wish I could just have the Sport mode level of power assist, without the Sport mode throttle. Any way to do that?
 

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While I didn't disconnect any wires, this seems very similar to the steering on my car. After I switched to 275's up front the steering got noticeably heavier, more than just fat tires would contribute to. I ran the codes and got got a "Servotronic Valve Current" code from my peake. It doesn't set of the SES light, but the code is always there.

I'm not sure if its a coincidence that this happened right when I switched to fatter tires or not. Either way, I haven't done anything to fix it, as I like the new steering feel. It isn't too heavy (for me) at parking lot speeds, and once moving it really is great.

So while it doesn't set off an SES, unplugging the wire may cause the Servotronic Valve Current code to come up. Not that it is necessarily bad, but just wanted to mention it.

So does this completely disable power steering? I took the P/S out of my Integra but can't imagine it with a heavier car with much wider tires!

I wish I could just have the Sport mode level of power assist, without the Sport mode throttle. Any way to do that?
No, it doesn't disable power steering. It just reduces the level of assist at lower speeds, offering a better feeling of connection to the road.
 

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Just did this "mod" today and drove for about 30 minutes. Definitely much heavier at low speeds, but not as noticeable after 20 mph. It's like having sport mode on at all times sans the super sensitive throttle. There is a small black box attached to the side of the car in the photo that I posted. You need to open it, and unplug the cable with the white connector (the one on the right side of the box). I left the longer part of it back in the box, and sealed off the other plug and zip tied it to the other cables. No codes showing on the dash of any kind.

Will leave it like this for a while and see how I like it. If anything changes, I will update you guys.
 

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Just did this "mod" today and drove for about 30 minutes. Definitely much heavier at low speeds, but not as noticeable after 20 mph. It's like having sport mode on at all times sans the super sensitive throttle. There is a small black box attached to the side of the car in the photo that I posted. You need to open it, and unplug the cable with the white connector (the one on the right side of the box). I left the longer part of it back in the box, and sealed off the other plug and zip tied it to the other cables. No codes showing on the dash of any kind.

Will leave it like this for a while and see how I like it. If anything changes, I will update you guys.
So is the steering effort just like with the Sport button, or heavier? From the descriptions it sounds like it's heavier than the Sport mode. I guess I could just try it lol.
 

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So is the steering effort just like with the Sport button, or heavier? From the descriptions it sounds like it's heavier than the Sport mode. I guess I could just try it lol.
Kind of hard to describe, but for a mod that you can do in 30 minutes yourself, just try it out :)

My best description is about 50%...yes 50% heavier up to about 20 mph...and then about 20-25% heavier after that. No more 1 handed parking :eek:
 

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Holy thread revival, Batman!

As part of moving to a standalone ECU, I will lose Servotronic steering in its stock form. I'd like to recreate it with a potentiometer that varies the amount of steering resistance or at the very least allows me to switch between a couple of levels of resistance. Did anyone ever figure out how to do this? According to WDS, there are two connections to the Servotronic: one entitled "A-T Servo" and one entitled "E-F Servo", each with relatively small gauge wire. Both connections run to the ECU and from the ECU to the center console switching center. Assume deletion of ECU and switching center. I clearly need to send power to the Servotronic, but am not sure how it works. My guess is that the connections are each high side drivers with relatively low current requirements (e.g., 1.5 amps). If so, then clearly I could connect a switch that would flow that level of current either to one connection or to the other, mimicking the impact of the Sport button. So: Does that seem correct to those who know this setup better than I?

--Peter
 

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Do you even try? :rofl:




Looks pretty straight forward - I am sure your stand alone can handle a changing current output.
 
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