Advancetrac is going to KILL me!
 

I have been having improper activations of the RSC/ESC system since March when we bought our 07 Limited. The first few times were when I would start to pull the boat up a hill from a STOP. The system would kill the power and caused me to roll back several times. I have to turn the system OFF now in order to get up the boat ramp.

During the first few months of ownership, the RSC came on and applied the brake pedal 2 times while driving on circular freeway onramps. I was going about 40 mph at the time and when I rested my foot on the brake, the pedal started pulsating violently. If you haven't had this happen yet, hold on. It can be pretty startling and seems likely to cause more crashes than anything. One time the RSC warning lamp stayed ON until the car was turned off an restarted. The dealer checked it out, said everything was normal, and "keep an eye on it". Well, I'm done "keeping an eye on it". Every week or so if I'm driving on a curvy road or onramp, when I tap that brake pedal, it slams back at me. I'm usually going about 40 mph when this happens and could probably being going 60 or so before the tires started to squeal.

I'm going back to a different dealer (our local FORD mysteriously closed their doors this month). I expect more of the same though. My last lemon took 9 months and a lawyer before Toyota agreed to buy it back. It cost them $2500 (for my lawyer) on top of the vehicle cost in the end. I hope Ford is more accomodating.

Any ideas what this might be? When we had problems with our Totoya Avalon, Toyota wouldn't authorize parts (a new ECU) because there was no error code being stored. Are there any components that are most likely to be the culprit? Are there adjustment that can be made to the system or a re-flash/re-program?

Thanks in advance. I want to go to the dealer a little prepared.

Seems virtually impossible that you would get two lemons in a row? I am on my seventh consecutive new vehicle, and although they all had problems, there was nothing to warrant me taking them back to the dealer with a lawyer. As far as the RSC, I did have one problem with my 06 Explorer, I was in a parking lot when it happened. One of the ABS senors in the rear driver's side broke, so if I tried to give the vehicle any gas, the drivers side front brake would intermittently lock up. Gouged my rotos a bit, but they wouldn't fix that, since the problem was in the rear.
I have subsequently traded the Explorer for the Expedition solely for size considerations since we had our second child, only one 900 miles, but no problems.

I would be curious if there are adjustments that can be made to the gyro associated with the RSC system? It sounds like your events weren't "random" but rather reacting to potential problems, i.e.-going around tight ramps/turns. It may just be set too sensitive?

Ok I have a crazy thought on this one.

What would happen if you installed heavier sway bars that reduced the body roll more then stock, Would that cut down and the feedback from the gyro as now the body isn't rolling as much?

Tmod

RE: the boat ramp, read the owners manual. With the system fully activated, the traction control part will reduce engine power. To prevent that from happening, you can turn off that part of the system with one tap of the ASC button. Then you have only braking traction control. That gives much more power to the non-spinning tire than a limited slip differential. However, it also says that if you are spinning the tires long enough, it will shut down to keep from damaging the brakes from heat. The owners manual also says to use 4wd or 4lwd on ramps if you have it. And, you should always go as slow as you can on boat ramps.

RE: the freeway ramp, you were going too fast and it was anticipating saving your butt. It "errs" on the early side to make sure that it can continue to keep saving you should you hit a road surface that has even less traction than the one you are already on, i.e. sand, water or ice.

Heavier anti-sway bars: the vehicle sensors measure acceleration in the major axes and roll-rate. The bars will just keep the body from rolling, but won't keep the sideways accereration from rising. In fact, the body will be rolling less when the stability control begins to help.

According to Ford the RSC does monitor body roll.

Tmod

Yes, but if the body rolls less, but the yaw angle is still wrong for the side ways acceleration and the tires are slipping at different rates, the control will still be working making decisions to prevent greater yaw angles, side acceleration and slip rates. The roll angle is just another parameter that it monitors for keeping in the safe range.

Very good posts rich93cw.

Thanks, the guy who wrote the federal motor vehicle safety standard worked for me. Hopefully some of that sunk in!

I'm looking at an 08 4x4. Can you pm some things to expect when i do things like go out in my muddy field with a trailor and get bogged. I like to work in mud, but I like to do so in Eddie Baur/Limited leather plush comfort :D

Since in the mud you are not going over 25 mph, then you can get it to work just like a regular 4x4H or 4x4L if you leave the traction control in the braking only mode. That way it applies all the torque to the tires with the most traction, as opposed to splitting the torque between the tire with traction and the one that is slipping. You just need to be judicious with the load pedal since it will be putting all the power to the tire(s) with traction and more likely to spin those, too.

I tried disabling the system with the button on the boat ramp, and it still causes the system to cut the engine power. I would expect it to operate that way, but in my case, there is NO tire slippage whatsoever. For some reason, it doesn't cut out if I put the transmission in "1" rather than "D" mode.

You got me there, that operation doesn't sound right, but I do remember that in one of the modes (2wd, 4wdH and 4wdL) it will start in 2nd, not 1st. I don't know what that has to do with the traction control still operating, with it turned off and no wheel slip.

Yea, it's pretty unnerving when you go to ease on the gas to pull 8000 lbs. up the ramp and the RMP's suddenly go to idle, then have to jam on the brakes in order to prevent rolling backwards.

Let me clarify, I have to disable the traction control by tapping it once AND put the tranny in "1" in order to prevent this. I'm thinking that the tranny position somehow disables the "engine power" aspect of the system.

Something must be wrong, because the Owner's manual says that a momentary tap on the switch should disable engine traction control and still leave braking traction control regardless of whether you are in 2wd, 4Auto or 4H. It doesn't say anything about having to be in 1st. Engine traction control is automatically disabled in 4L.

On my 2005 explorer (the expy might be different but probably shouldn't be that different):

push RSC button and release: braking traction control mode
push and HOLD RSC button for at least 5 seconds: everything off. The "off" light in the button will flash. It might engage if a very high threshold is reached, but luckily I've never had that occur.

4X4 auto and high: does nothing; uses whatever setting the button is in
4X4 low: automatically goes into traction only mode. You can shut this off by holding the button as explained above.

Trust me, I've tested all these settings in a snowy parking lot. This is what mine does.

I agree though- if I'm in an intersection about to get t-boned I would rather skid and be able to accelerate than have my throttle cut and get t-boned.