Hi
I'm hoping someone can shed some light or maybe even has experienced something similar themselves.

I own a (purchased new) 2015 Outlander XLS and while driving my children to school yesterday the ASC light flashed on the dash, slowed my vehicle right down within seconds (it was noisy), I lost the steering and the brakes locked - I lightly touched brakes to stop completely but the brake was hard (assume this is locked) and it was similar to slamming the brakes on in an emergency. Luckily for me there was a car some distance behind me as I couldn't even pull off the road before the steering went. I was on a straight road in dry conditions doing between 60-70km.

I pressed the ASC button a few times before the flashing stopped - at no time did the light become solid. Then pulled out slowly only for the light to flash again approx 5 meters further up the road. It did start to slow the car but I pulled over and pressed the button again a few times. Pulled out again and drove in an 80km zone to school.

The ASC light flashed once before - maybe 3 months ago (could be longer) and I pressed the ASC button while driving and it corrected itself.

The car was taken into the dealer who ran the diagnostic but as the light never became solid it didn't register on the computer. They have tried to replicate the situation to no avail so they are unsure what the problem is. They have said they've checked the throttle fully and everything appears as is.

Has anyone every experienced anything similar or can suggest what has happened? I am nervous that this may happen again when I am in traffic, especially as the festive season approaches and it could have dire consequences if a truck was behind me.

 

Have you hit/driven over anything solid in the road? I hit a chunk of metal in mine years ago that did damage to the brake components including damage to the wheel sensor cable. If all four wheel sensors are not reporting correctly, the car will freak out. It believes there is a wheel out of control and does it's best to get all four wheels back to the same speed. Including reducing throttle and applying the brakes. Makes the dashboard go crazy too. See if the dealer is willing to inspect the cables and connectors, also if they will drive it with the diagnostic laptop hooked up and check the incoming values from the wheel sensors. Hope that helps a bit

 

Thanks binzd.
No I haven't hit or driven over anything solid at all. The dealership have had the car for nearly a week and driven around town, motorways, and rural with the diagnostic laptop connected and they have said nothing is amiss. They asked what type of roads I drive on and if they were extra bumpy. I did mention wheel sensors but they didn't think that was the case. It has been explained to me that ABS and ACS came into affect but why is the unknown and will it happen again??? who would know as it hasn't registered in the computer.
Thanks so much for taking the time to read and suggest something, most appreciated.

 

Boy, there is nothing worse than an intermittent problem. Makes you looks crazy when the cars goes to the shop. I am not sure how the Outlander logs ABS/ACS events (in the case of the emission system, it has a freeze frame report where you can see all the operating values to use in diagnosis). As far as the dealer remaining "mystified", you might want to ask them to use an actual factory fault tree. I am attaching the Service Manual chapter for a little light reading. Some of their documentation is worse than legal documentation. But it has values to test.

Item Standard value
Wheel speed sensor current mA 5.9 - 8.4 or 11.8 - 16.8
Wheel speed sensor insulation resistance MΩ 5 or more

The most common scenario for a "ghost in the machine" is a bad ground. Especially if two systems share a common grounding location. Corrosion can build up, thus causing a lack of voltage in the circuit and the computer module will read the value incorrectly (such as a wheel sensor showing a lower value and tricking the module into thinking the wheel is not spinning). A loose ground is also possible or a ground that was replaced after body work or accident repair where the post was painted by mistake (also very common).

The only other sensors that ABS and ACS rely on are the pitch/yaw sensors and steering angle sensors (of course the throttle and brake are monitored too, but more as a function of if the driver wants to go or stop not, is the car sliding or tipping). The pitch/yaw sensors are located all throughout the cabin, I found one over the back wheel hump when replacing shocks two years ago. Any kind of aftermarket installation or stereo work inside of the car?

As far as road confidence, perhaps there is a fuse you can pull to stop power to the ASC/ABS module if you end up stranded? This is not ideal for many reasons, (I'm not the best driver here so I wouldn't do it, but I also wouldn't want to be sitting on the side of the road, miles from civilization).

As far as the dealer network is concerned and as they say in the American South, "Bless their hearts." They mean well, but corporate does not see that the techs are properly trained and the customer service levels vary from ok to dismal. I have to drive 45 miles to one particular dealer if I just want an alignment. It's a shame, because they are such well engineered and built autos, with more support for customers, they would retain regular customers instead of fanatics like me.

Good luck and stay persistent. Cheers

 

Thank you again bindz.

Might have to pass the light reading on to my hubby - not that he is technical at all!
We've had no aftermarket work done at all - and the car is only 17 months old and purchased new (6km reading).

Update so far is the dealer is in contact with the HO in NZ (a very small market for Mitsubishi obviously) speaking with the technical teams trying to assess what initiated the problem - and wheel sensors were the first thing they were advised to do a complete overhaul on! Your suggestion was right the first time.

Apparently they have been cleaned thoroughly and reinstalled. The next thing they did was put the diagnostic laptop on again and take if for another run and here they found that there was a slight stickiness with the brake switch - possibly 2-3 seconds. The dealer and the technical team at the HO feel this was sufficient constructive feedback for the cause of the problem and are confident the issue is corrected.

As for my thoughts - I feel a loss of confidence in the car and would not take the car with my children or other people's children on the motorway, highways or rural roads. I might venture around town but we'll see.

 

There was a recall on brake switches for other years, I would certainly think they can afford to replace the relatively inexpensive part for you whether it's covered or not. Good luck.