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Discussion Starter · #1 · (Edited)
My car does not appear to be happy with cold weather and I'm not sure what's going on.

So I know about the drive modes having issues when the car starts in freezing temps (which is ridiculous enough but whatever, at least it works).

Except that now my car isn't working. I wasn't drifting in the snow, racing, anything. It tends to sleep in a garage at night except for very rarely when I need to leave it out for one reason or another. Anyway, I started my car up in my driveway and basically everything isn't working: ABS error, AWD error, traction control error, hill assist error, naturally the drive modes are disabled as well. The car does start and does move but it's a front wheel drive with too much torque, no differential, no traction control or ABS in the winter. So while I could probably get it to the dealership the safer decision probably means having it towed given the snow and ice we have here right now. The weirdest part is less than 30 minutes earlier the car was out for a shopping run just fine. The temps hadn't even cooled all the way down and yet here we are.

There are no typical "service" errors however, such as a check engine warning.

Naturally I've tried bringing the car fully to temperature, shutting it off and on (with various delays in between), etc.

Anyway, I was wondering if anyone has had this issue or can think of a solution before I take it in. Is there a sensor of some kind that might have gotten dirty? Something like that. On a normal car I might try disconnecting and reconnecting the battery but I'm unfamiliar with the special battery type/system in this car and I wasn't sure if that was a good idea.

Thanks in advance to anyone who can help!
 

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Take it into Ford and ask them why is this occurring. Sounds electrical.

Good luck :thumbsup:
 

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I had the same thing happen to my RS around 4000 miles last year. The abs sensors on all four wheels were coved in rust that had run off of the hub assembly that they are mounted in. I removed all four sensors and cleaned the rusty residue off of them and the errors cleared and have not returned again. I now have 18000 miles on my RS. The rusty residue was causing the abs sensors to malfunction. Good luck.
 

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Discussion Starter · #4 ·
Update:

So this has been happening to me for a full week at this point. Dealership was booked until today. So I got it on a truck and shipped over to them. I **** you not, when we turned it on to roll it off the truck, the errors didn't come back on. Dealership checked it anyway and while they saw the warnings in the history could find no system faults.

I'll keep that in mind about the ABS sensors. I have a feeling my problem was being caused by something loose and/or crusty. Either way the problem seems to have cleared for now. I wonder if the ride over knocked whatever it was back in to place.
 

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I just got the same errors yesterday. No AWD, Hill Assist, or Drive mode selection. ABS and Traction Control lights stay on. No check engine light, but when I scanned the car with my ob2 scanner the following codes came up: C0051 Steering wheel position sensor, C003A Right Rear wheel speed sensor, and U0418 Invalid data received from brake system control module A. I checked the right rear wheel speed sensor, and cleaned it off. Errors still persist.

I live in California, and the coldest it has been is around 40F. Car is parked in the garage at all times. It was fine the last time I drove it which was last Thursday. I haven't tracked it or drifted in it. I've only used launch control a few times. I don't know what it could be. Going to make an appointment with the dealership tomorrow.
 

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I have the same problem. First appeared 3 months ago, the dealership has no clue about what's causing the problem :nightmare: they've replaced a sensor, reset the control module with no success... and i'm waiting for them to call me in order to replace the abs pump or whatnot...
Still, driving a FWD RS (in the winter in particular), is not very pleasant :distrust:
 

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Do you people have any updates on what the problem was ?
My dealership keeps changing parts, but this issue keeps coming back...

I had the same thing happen to my RS around 4000 miles last year. The abs sensors on all four wheels were coved in rust that had run off of the hub assembly that they are mounted in. I removed all four sensors and cleaned the rusty residue off of them and the errors cleared and have not returned again. I now have 18000 miles on my RS. The rusty residue was causing the abs sensors to malfunction. Good luck.
Did you clean just the black connector or did you take of the whole sensor ?
 

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I removed the wheels speed sensors at each wheel and cleaned off the whole sensor. I checked the plugs and electrical connectors at each sensor and the were all in good shape and not contaminated. I suspect the rusty residue on the side of the sensor that faces the exciter rings was causing faulty outputs from the sensor. It has been 12000 miles since I had this issue and it has not returned.
 

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My issue was due to a stupid rat or mouse chewing some wires
 

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Check the earth leads.
Good luck.
 

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My car does not appear to be happy with cold weather and I'm not sure what's going on.

So I know about the drive modes having issues when the car starts in freezing temps (which is ridiculous enough but whatever, at least it works).

Except that now my car isn't working. I wasn't drifting in the snow, racing, anything. It tends to sleep in a garage at night except for very rarely when I need to leave it out for one reason or another. Anyway, I started my car up in my driveway and basically everything isn't working: ABS error, AWD error, traction control error, hill assist error, naturally the drive modes are disabled as well. The car does start and does move but it's a front wheel drive with too much torque, no differential, no traction control or ABS in the winter. So while I could probably get it to the dealership the safer decision probably means having it towed given the snow and ice we have here right now. The weirdest part is less than 30 minutes earlier the car was out for a shopping run just fine. The temps hadn't even cooled all the way down and yet here we are.

There are no typical "service" errors however, such as a check engine warning.

Naturally I've tried bringing the car fully to temperature, shutting it off and on (with various delays in between), etc.

Anyway, I was wondering if anyone has had this issue or can think of a solution before I take it in. Is there a sensor of some kind that might have gotten dirty? Something like that. On a normal car I might try disconnecting and reconnecting the battery but I'm unfamiliar with the special battery type/system in this car and I wasn't sure if that was a good idea.

Thanks in advance to anyone who can help!
I had same problems as yours.
I live in Australia and temperature aren’t too cold .it’s a problem caused by the abs sensor and it needs to be replaced .
Weren’t able to tell me what caused the problem or the break up of it.
Yeah car is totally useless when this fault happens.
 

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Have had the same issue with my car for several years with extended trips to the dealer which could "not reproduce the error"

I've figured out that, in my instance, temperature isn't a factor, rather, my driveway is on a slight incline. When I pull up and park, the hill start assist engages, I pull the ebrake & shut the car off. As the car shuts off, the hill start disengages and the car will squeak back just slightly onto the ebrake (less than an inch of movement). If I hit the start button again (clutch or no clutch) the same errors present with a number of codes.

  1. p08b2-00 - Neutral position sensors A/B correlation
  2. u0151-00 - Lost communication with restraint control module
  3. u0136-00 - Lost communication with differential control module - rear
  4. u0102-00 - Lost communication with TCCM
  5. u0418-00 - Invalid data received from brake system control module A
If I drive the car anywhere from a few ft to the longest has been ~1/2 mile or so, the errors will clear, AWD re-engages, and I can then change drive modes.

Car goes back to the dealer shortly for further diagnostics.
 

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Have had the same issue with my car for several years with extended trips to the dealer which could "not reproduce the error"

I've figured out that, in my instance, temperature isn't a factor, rather, my driveway is on a slight incline. When I pull up and park, the hill start assist engages, I pull the ebrake & shut the car off. As the car shuts off, the hill start disengages and the car will squeak back just slightly onto the ebrake (less than an inch of movement). If I hit the start button again (clutch or no clutch) the same errors present with a number of codes.

  1. p08b2-00 - Neutral position sensors A/B correlation
  2. u0151-00 - Lost communication with restraint control module
  3. u0136-00 - Lost communication with differential control module - rear
  4. u0102-00 - Lost communication with TCCM
  5. u0418-00 - Invalid data received from brake system control module A
If I drive the car anywhere from a few ft to the longest has been ~1/2 mile or so, the errors will clear, AWD re-engages, and I can then change drive modes.

Car goes back to the dealer shortly for further diagnostics.
What work have you done to the car? My bet is that you have some bad electrical grounds.
 

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What work have you done to the car? My bet is that you have some bad electrical grounds.
Sadly - no major mods (Velossatech big mouth, mountune intake, mountune BPV, Rally Armour mudflaps.) There is a plethora of power goodies in my basement taunting me...but not going on until they figure this out.

This has happened since I purchased the car which was previously owned by an older gentleman with zero mods.

Dealer has "checked all connections for corrosion and re-seated. They have also done the TSBs for the exhaust valve.

A local friend has an RS (has only had the errors once) and we tried in the exact locations the same steps to reproduce. Cannot reproduce with his.
 

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Sadly - no major mods (Velossatech big mouth, mountune intake, mountune BPV, Rally Armour mudflaps.) There is a plethora of power goodies in my basement taunting me...but not going on until they figure this out.

This has happened since I purchased the car which was previously owned by an older gentleman with zero mods.

Dealer has "checked all connections for corrosion and re-seated. They have also done the TSBs for the exhaust valve.

A local friend has an RS (has only had the errors once) and we tried in the exact locations the same steps to reproduce. Cannot reproduce with his.
Weird. Grab an electrical diagram and see if there are common power sources or ground points. I know that around the car there are poor ground points, one being in the rear hatch on the driver's side. Many of the ground points are painted and rely on the threads cutting the paint for the electrical connection. Bad grounds on the frame rail under the airbox have caused all sorts of weird issues, for example.
 

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My car does not appear to be happy with cold weather and I'm not sure what's going on.

So I know about the drive modes having issues when the car starts in freezing temps (which is ridiculous enough but whatever, at least it works).

Except that now my car isn't working. I wasn't drifting in the snow, racing, anything. It tends to sleep in a garage at night except for very rarely when I need to leave it out for one reason or another. Anyway, I started my car up in my driveway and basically everything isn't working: ABS error, AWD error, traction control error, hill assist error, naturally the drive modes are disabled as well. The car does start and does move but it's a front wheel drive with too much torque, no differential, no traction control or ABS in the winter. So while I could probably get it to the dealership the safer decision probably means having it towed given the snow and ice we have here right now. The weirdest part is less than 30 minutes earlier the car was out for a shopping run just fine. The temps hadn't even cooled all the way down and yet here we are.

There are no typical "service" errors however, such as a check engine warning.

Naturally I've tried bringing the car fully to temperature, shutting it off and on (with various delays in between), etc.

Anyway, I was wondering if anyone has had this issue or can think of a solution before I take it in. Is there a sensor of some kind that might have gotten dirty? Something like that. On a normal car I might try disconnecting and reconnecting the battery but I'm unfamiliar with the special battery type/system in this car and I wasn't sure if that was a good idea.

Thanks in advance to anyone who can help!
I had the same problem as you did,with the exception I m living in Australia and weather isn’t cold during winter ,so my problem wasn’t because of the freezing temperatures.
Anyway they replaced the rear sensor without telling me what caused the problem.
Car seems fine since then and is back to normal.
Good luck with that
 

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Anyone have a good diagram source available. The more free the better!?!

I'm leaning towards sensor(s) in the rear. I can consistently reproduce the issue with the slight (less than inch) movement as it settles into the e-brake, either backward, or when I had the back on ramps, forward.

Fingers crossed this last time is the fix as my car spends entirely too much time at the dealer (~2hrs away)
 

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So...has anyone here figured out their issue? Just got the same exact issue on my way home from work while on the freeway. Thankfully the car was still drivable and was able to get all the way home. On one hand I'm glad I'm not the only one who's had this issue but on the other hand I'm a little worried that I'm yet to find a definite fix.
 

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Alright, replying to my own post with what I've found so far. Fired up FORScan and pulled a handful of DTC's

P08B2 - Neutral Position Sensor A/B Correlation (I've had this pop-up every once in a while)
C0034 - Right Front Wheel Speed Sensor
U0415 - Invalid Data Received from Anti-Lock Brake System (ABS) Control Module A
U0418 - Invalid Data Received from Brake System Control Module A
U0140 - Lost Communication With Body Control Module

So...it sounds like my next thing to look at is the wheel speed sensor. Hopefully its just a loose connection or something.
 
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P08B2 definitely isn’t responsible for those issues, had this one for probably most on my car’s life with no adverse effect 🤣

Seems you figures it out already! Reminds me of my ‘10 sti which light up every single light in the cluster and killed the abs/cruise everytime a single CEL came up!

Good luck with the fix!
 
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