MARK 99STS Posted August 8, 2005 Report Share Posted August 8, 2005 Well I have successfully gotten around traction control. It is very simple if you want to permanently defeat traction control and ABS as they are tied together. Now I can't speak for all models, but I would assume they are the same. All you have to do is pull the connector off each wheel sensor and put a 1000 ohm resister into the connector. No codes, no other issues. Unfortunately this eliminates both traction control and ABS permanently. I have the guy working on a board with relays to be able to switch back and forth. I will keep you posted. MARK 99STS TURBOCHARGED Link to comment Share on other sites More sharing options...
WarrenJ Posted August 8, 2005 Report Share Posted August 8, 2005 It is very simple if you want to permanently defeat traction control and ABS . . . . Unfortunately this eliminates both traction control and ABS . . . . Homer said it best: "D'oh?" There is no means of avoiding the final collapse of a boom brought about by credit expansion. The alternative is only whether the crisis should come sooner as the result of a voluntary abandonment of further credit expansion, or later as a final and total catastrophe of the currency system involved. - Ludwig von Mises Link to comment Share on other sites More sharing options...
JasonA Posted August 8, 2005 Report Share Posted August 8, 2005 Mark, I know you've been working on that for a long time, and I'm glad you found a "breakthrough" (pun intended--see recent Cadillac ads). From how you describe, it sounds like you could easily have a 1k ohm resistor in parallel with a straight wire, with a switch at the driver seat. Good luck, Jason(2001 STS, White Diamond) "When you turn your car on...does it return the favor?" Link to comment Share on other sites More sharing options...
danbuc Posted August 9, 2005 Report Share Posted August 9, 2005 F'n Sweet! I know what my project for the month is. Well, I'm off to Radioshack at some point this week to get supplies. Four 1k ohm resistors, four miniature relays to be mounted inline with the wire leading from the connectors, to the PCM, and four control wires linked to a central switch in the dash that will ground all four relay coils at the same time. It should work quite well I imagine, if everthing goes according to plan. edit:Now are the resistors going into the connectors for the Vehicle Speed Sensors, or something else. If they are going int o the connectors for the VSS, how does the speedo work, or anything eles governed by vehicle speed? Just curious to find out all the details befor I go messing with it. Let me know before hand, so I can look in my service manual to see what I'll be going after under there. Link to comment Share on other sites More sharing options...
WarrenJ Posted August 9, 2005 Report Share Posted August 9, 2005 Well, I'm off to Radioshack at some point this week to get supplies. Four 1k ohm resistors, four miniature relays to be mounted inline with the wire leading from the connectors, to the PCM, and four control wires linked to a central switch in the dash that will ground all four relay coils at the same time. It should work quite well I imagine, if everthing goes according to plan. This sounds like swatting flies with a 12 gauge. I'd guess there's a simpler more "elegant" solution. Perhaps someone with a wiring drawing might care to post? Regards, Warren There is no means of avoiding the final collapse of a boom brought about by credit expansion. The alternative is only whether the crisis should come sooner as the result of a voluntary abandonment of further credit expansion, or later as a final and total catastrophe of the currency system involved. - Ludwig von Mises Link to comment Share on other sites More sharing options...
JasonA Posted August 9, 2005 Report Share Posted August 9, 2005 edit:Now are the resistors going into the connectors for the Vehicle Speed Sensors, or something else. If they are going int o the connectors for the VSS, how does the speedo work, or anything eles governed by vehicle speed? I think the VSS is in the transmission, at the tailshaft. I think the individual wheel sensors only play with ABS, TCS, and ICCS. I imagine that by disconnecting these sensors, your StabiliTrak will also be disabled. Jason(2001 STS, White Diamond) "When you turn your car on...does it return the favor?" Link to comment Share on other sites More sharing options...
danbuc Posted August 9, 2005 Report Share Posted August 9, 2005 Ehh...who needs stabilitrak if your not turning, and your on nice dry pavement (famous last words..hehe). If the Wheels speed sensors only govern ABS and traction control, than that's not a problem. WarrenJ, having four tiny relay's is the only real way I can see to switch between to different input on four seperate wires at the same time. Granted running all those wires will be a real pain, but as long as all four relay's and the switch have a good power and ground source, it should work flawlessly ever time. These relay's are small enough that when wired in, they could easily be concealed by shrink tubing to protect them. All four could then be run through a single switch in the dash, used to control power to each relay's coil. Once you flip the switch, all four relay's would close, bypassing the circuit directly through the 1k ohm resistor, instead of the connector. It is kind of complicated, but overall a pretty straight foward design. Link to comment Share on other sites More sharing options...
Oldgamer Posted August 9, 2005 Report Share Posted August 9, 2005 I rather not to shut off ABS and tracktion control, but anyway there is a better solution. It's possible to have just one relay with enough switching contacts, and relay and resistor can be installed somewere close to computer, so you don't need in long wiring. Link to comment Share on other sites More sharing options...
Oldgamer Posted August 9, 2005 Report Share Posted August 9, 2005 P.S. You can disable traction control on a car has computer with OBD 1 just making override. It will work for 11 ignitions cyckles wich is enough in most cases. I don't know if it possible on a cars with OBD 2, though. Link to comment Share on other sites More sharing options...
danbuc Posted August 9, 2005 Report Share Posted August 9, 2005 This is true, all you would need to do is identify which pins lead into the harness at the PCM. The only problem I can see if how will you control four seperate signals with one relay. The relay istelf will only have 3 usable contacts. Running four seperate circuits through one 1k ohm resistor might not work. With a small relay at each connector, you would only be running four wires to the switch for power. The ground wire for both the switch and relay's can go right to chassis ground. I suppose you could mount all four relay's up near the EBTCM which would get rid of the need to run wire from outside to inside the car. With one relay, you have alot more wiring, since you have to link it to each circuit, and then splice them all together. This means, that even with the relay turned off, all four signal will be mixed once they reach the single contact at the relay, and then scrambled going out to the EBTCM. Your ABS and T/C probably wouldn't work then even with the relay turned off. With four seperate relay's you keep each circuit seperate, effectively preventing any interference you would have with splicing all four signals wires together. Here's the wiring schematic out of the service manual Link to comment Share on other sites More sharing options...
Oldgamer Posted August 9, 2005 Report Share Posted August 9, 2005 danbuc, I didn't want to have one resistor, just one relay with all contacts separate. If all pairs of contacts are separate signals will not mix. It was my mistake when I wrote "and relay and resistor can be installed". I meant "and relay and resistors can be installed". So, one relay and 4 resistors will make it. Link to comment Share on other sites More sharing options...
MARK 99STS Posted August 9, 2005 Author Report Share Posted August 9, 2005 Danbuc, We plugged the resistor directly into the speed sensor connector. All other input data(speedometer,etc. comes from somewhere else as everything worked as normal with no codes. I assume this would kill stabilitrack also which is why I want to switch it. Like you said, I can live without ABS,TC,and Stabilitrak in a controlled situation at the track or flat dry road. The wires to tapp into are directly from the harness plugged into the ABS unit under the PCM. If you take out the air box and lay the PCM over to the side, you can unplug the harness at the ABS and pull it right up to work on it. Piece of cake. There are four braided pair that are the wheel sensor wires.(see service manual) My colors weren't exactly right, but there are only 4 braided pair so you can't go wrong. We confirmed this with a meter going pin to pin. He is talking about putting everything on a board and house it under the dash with a switch and run the wires directly to the harness at the ABS unit. MARK 99STS TURBOCHARGED Link to comment Share on other sites More sharing options...
danbuc Posted August 9, 2005 Report Share Posted August 9, 2005 danbuc, I didn't want to have one resistor, just one relay with all contacts separate. If all pairs of contacts are separate signals will not mix. It was my mistake when I wrote "and relay and resistor can be installed". I meant "and relay and resistors can be installed". So, one relay and 4 resistors will make it. The only problem is finding a relay with enough contacts to make that work. I suppose if one were to wire up a couple of transistors on a board with all four resistors attached, that would really be the best way. Mark, I guess that's what that guy you are working with is reffering too. Also, having a solid state transistors instead of a relay would make it much more reliable as well. Plus, you could build a seperate harness for it or soemthing, so that if you wanted to pull it out, it would be much easier to remove. Link to comment Share on other sites More sharing options...
KPierson Posted August 12, 2005 Report Share Posted August 12, 2005 Hi all. My name is Kevin, I'm the guy that has been working with Mark on this project (we share a love for FI ) Unfortunately, the solution is not as simple as it appears to be. You will actually need 8 sets of switchable contacts, because you will need to basically replace the wheel sensor with the resistor. In the short amount of time I had to play with Mark's Caddy I found that the wheel sensor itself appears to be a coil (hence the 1,000 ohms) and there must be several very strong magnets mounted in the rotor. As the wheel spins the magnets pass the coil and create a very low voltage, AC signal (2 volts peak to peak from memory). The frequency of this signal is changed based on speed. We did find out that if at any time the car loses 'sight' of the 1,000 ohm wheel sensor coil it will throw a code, as it is continously monitoring each sensor. What I plan to do is to find 4 DPDT relays and mount them in on enclosure. We'll then run two cat5 cables from the box mounted under the dash to the ABS computer. We'll have to cut ALL 8 wires for the wheel sensors. We'll reconnect the front two wheels to one cat5 cable and the rear wheels to the other cat 5 cable. In 'normal' mode the cat5 cables will pass through our relay box. When you push hte push button the relays will energize and will break the connection to all wheel sensors and replace them with the 1,000 ohm resistor. I may get fancy and include a small LED to indicate 'track mode.' The whole setup will operate like the OEM traction control system. Its very unfortunate that Caddilac engineered such a sophisicated system, but I must give them credit for the overall functionality of the system, and the very accurate error dectection! Link to comment Share on other sites More sharing options...
JasonA Posted August 12, 2005 Report Share Posted August 12, 2005 Welcome Kevin! Hope to see you back here soon again. I understand the "unfortunateness" that the system is so sophisticated from a modifier's standpoint, but on a daily basis with most normal drivers, Cadillac's traction control system is about as effective as it gets. I've never experienced a better one, short of 4 wheel drive! Cheers, Jason Jason(2001 STS, White Diamond) "When you turn your car on...does it return the favor?" Link to comment Share on other sites More sharing options...
TDK Posted August 13, 2005 Report Share Posted August 13, 2005 Well, I still say just mount another sensor to one of the front wheels and relay the sensor wires from the other front wheel to it in dragstrip mode. Switch the relay back to normal when on the road. Or forget any relay and reach in to switch sensor plugs with a longer signal wire. I don't think the traction control works unless the front wheels are over 5% differant. So fool the system into thinking one front wheel is both. Maybe the stabitrack gets more complicated...but, this method is cheap to try and easy to undo. All IMHO Good luck Add power to leave problems behind. Most braking is just - poor planning. Link to comment Share on other sites More sharing options...
KPierson Posted August 13, 2005 Report Share Posted August 13, 2005 I would be hesitant to run one sensor to multiple inputs, as the current generated by a wheel moving can not be significant. Not knowing what kind of input stage the ABS computer uses (transistorized I would imagine) we have no idea to know the limitations of the sensor and ABS inputs! I think adding a sensor to the front wheel would be a LOT of work. The Caddy doesn't use the same type of sensors that other cars use (or at least that I have seen). Most cars use a 5vdc signal and basically a reed switch to send a DC square wave back to a monitoring computer. Most systems don't have the feedback feature of the 1K ohm coil! Kevin Link to comment Share on other sites More sharing options...
danbuc Posted August 13, 2005 Report Share Posted August 13, 2005 It's probably a magnetic pickup Hall-Effect type sensor. Alot of cars use them, where it uses the changing gap between the teeth around the wheel side of the CVD (or wheel hub,..ect) and the coil in the sensor to generate an weak electrical signal. This then pulses through the cunductor to the module and read as a digital signal I think with the restors, your basically fooling the ABS module into thinking thst the car is not moving. As long as the input isn't used for any other systems, your idea of bypassing all four cicuits should work just fine. Let us knwo when you get something fabricated. I myself would definitely be interested in purchasing such a product if you succesfully develop it. Link to comment Share on other sites More sharing options...
TDK Posted August 13, 2005 Report Share Posted August 13, 2005 KPierson, Your note..." I would be hesitant to run one sensor to multiple inputs, as the current generated by a wheel moving can not be significant. Not knowing what kind of input stage the ABS computer uses (transistorized I would imagine) we have no idea to know the limitations of the sensor and ABS inputs"...demonstrates a possible misinterpretation of what I tried to convey. I did not mean to use one "sensor" to two computer inputs. Simply install a second sensor from a junkyard. There would be one sensor for each front wheel input, but of course they would both be on the one wheel (so no speed difference). The sensing technology might not be based on a magnet in the hub itself or even any small square wave current being generated. Probably too simple for Caddy it would seem to me. I recall that the Caddy has a toothed bearing hub that is relatively expensive (there may be a reason, beside the label). Since it is used for high speed calcs; like traction control and stabilitrack - the computer probably needs the highest frequency possible. This would provide more signal resolution than what is available with a single magnet and one pickup that fires once every rotation. The 1,000-ohm coil might be a the end component of a magnetic flux-field sensor that develops a signal from the rotation of the toothed hub. Basically, it counts each of the steel teeth as they are rotating past. A bonus is that with a quasi-calibrated, fixed resistance coil/antenna, it can be instantly detected as missing (unlike a simple switch or square wave DC pulse). This entire setup could be a variation of a "key-phaser" speed pickup signal used in vibration analysis equipment (no magnets required). A Key-phaser is a fundamental speed signal and can also be used to index a given shaft position relative to vibration signal (from proximity-type voltage probes mounted radially and axially for thrust) on a O-scope. This is not really my forte, (as demonstrated by my limited knowledge), so please consider all this proposed techno-BS with some trepidation. However, it seems more plausible BS, than any magnetic pickup or of course a relatively crude reed switch. Again, all IMHO. Good Luck Add power to leave problems behind. Most braking is just - poor planning. Link to comment Share on other sites More sharing options...
Oldgamer Posted August 13, 2005 Report Share Posted August 13, 2005 The system with relay still will have some limitation possible. I'm not sure, but it's possible that it will throw a code in a moment of switching if ignition is on. For very short time computer input will be disconnected from both, sensors and resistors. But possible that time will be short enough not to throw a code and everything will be fine. Link to comment Share on other sites More sharing options...
danbuc Posted August 13, 2005 Report Share Posted August 13, 2005 I guess if that's the case you could just power the relay's directly off of the battery so that you could switch with the car off. That way it would already be runing through the resistors when you start the car. Link to comment Share on other sites More sharing options...
KPierson Posted August 14, 2005 Report Share Posted August 14, 2005 Adding a 2nd sensor might not be that bad of an idea. The ABS sensor is mounted right next to the brake pad sensor. Mark has permanently bypassed his pad sensor, and by doing so it can be physically moved. In its place, you might be able to mount another sensor, but, I'm not exactly sure how it all works, as we never took the tire off. Each time I messed with the sensors I just slid under the jacked up car. I don't think there will be switching issues. The relays I'm looking at switch in approximately 6ms, which is an eternity to a microcontroller, but insignificant to the real world. It is my hope that the Caddy computer has enough filtering and error checking that it won't jump the gun if a sensor is missing for 6ms! I may be wrong on this though. For I think the fourth time now I have changed the hardware design. I'm in the middle of building the new prototype circuit to test out on my car (Its an Infiniti and much, much simpliar of a system) but I feel that the technology I'm implementing will go both ways, I will just need more outputs on the Caddy version. I really would like to get away from switching ALL 8 wires. I would like to see a system that still monitors two wheels, and mimics those two wheels to the front wheel inputs. If we can do it without adding additional sensors that would be best, but in the end the additional sensors may be a good route to take. My main concern is lining them up correctly and keeping them aligned. Back to work I go.... Mark, sorry I missed your call today, I will call you back on Sunday. Link to comment Share on other sites More sharing options...
navion Posted August 14, 2005 Report Share Posted August 14, 2005 There is a simpler way! On the brake fluid reservoir there is a low fluid level indicator. It has a connector that plugs in at the lower left side of the reservoir. If the indicator detects a low brake fluid condition it will automatically disable the traction control and, unfortunately the ABS as well. Instead of going with multiple relays and resistors, why not just disable the brake fluid level sensor? The results will be the same, and with a lot less work! Britt Britt Link to comment Share on other sites More sharing options...
KPierson Posted August 14, 2005 Report Share Posted August 14, 2005 Our main objective was to disable the system without throwing any codes or warnings. We already found out that if you simply disconnect a wheel sensor the system will NOT work. However, a side effect of the ABS not working is that the car will automatically start in 2nd gear. This is unacceptable. If the car thinks ABS is working then you can launch in 1st gear, WITH wheel spin. Link to comment Share on other sites More sharing options...
WarrenJ Posted August 15, 2005 Report Share Posted August 15, 2005 There is a simpler way! On the brake fluid reservoir there is a low fluid level indicator. It has a connector that plugs in at the lower left side of the reservoir. If the indicator detects a low brake fluid condition it will automatically disable the traction control and, unfortunately the ABS as well. Instead of going with multiple relays and resistors, why not just disable the brake fluid level sensor? The results will be the same, and with a lot less work! Britt Afraid I'm not following that . . . . Regards, Warren There is no means of avoiding the final collapse of a boom brought about by credit expansion. The alternative is only whether the crisis should come sooner as the result of a voluntary abandonment of further credit expansion, or later as a final and total catastrophe of the currency system involved. - Ludwig von Mises Link to comment Share on other sites More sharing options...
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