crazych42

OK I have had my car for two months and haven't really had an issue with the PCS... until today. Yes, I have gotten a couple random "false positives" where the warning light would come on but it has never intervened. This time was different. I have read on here previously where someone had an issue merging into traffic and I can now relate. Firstly, I take full responsibility for the issue. The PCS worked as advertised, I just unwittingly put the car and me in a situation where an accident could have happened.

Here is the scenario. I'm driving on the interstate and am in the right lane and about to overtake a slow SUV in the left lane (it is VA... cars hang out in the left lane and don't move over ). As I am overtaking the SUV I'm quickly approaching a slow car in front of me in my lane. I make the decision to accelerate past the SUV in the left lane to try and get in front of it. As I hit the gas, accelerated and approached the car in front of me to try and get in front of the SUV my closing speed was obviously too fast. As I got close to the car and right as I was about to change lanes the PCS warning started screaming... Keep in mind this was happening in mere seconds at 80mph. Unfortunately I had already committed to the lane change and was completely ignorant to what the PCS would do. Guess what happened? Yep, that's right...he PCS applied the brakes... HARD right after I changed lanes and I went from 80 to 60 in a sec. Fortunately the SUV I pulled in front of reacted quickly and didn't hit me else it would have been bad. I had my foot on the gas the whole time hoping the car would accelerate and eventually the PCS disengaged and I was on my way....

Just a caution to those with PCS... be careful in situations where you are quickly approaching slower moving traffic and expect to change lanes quickly....as the PCS could intervene when you do not expect it to and put you in a precarious situation.

Mr_VFS1

Glad you're ok but that sounds really scary. I would've soiled my pants if I were you.

corradoMR2

This is excellent information to share. Glad there was no incident. Hopefully the guy behind you didn't pull a finger or engage in any road rage for your sudden (unwanted) braking. Moving forward, would you disable PCS for a planned passing situation such as the one you were in?

ISDAS

that sounds.......horrible..

drive90

I am one of the ones that has had this happen to, but I was in stop and go traffic in Miami on surface streets. Tried to pop in between two cars in a gap I spotted and the person to my right whom I tried to pass nearly rear ended me when my PCS engaged.

I hear a tap of the brakes will kill it... but that's untested by me.

jennypenny

i guess, PCS is great but if you are weave in and out (like in your case), it may be worser off with it.

i wouldnt blame the PCS for doing its job.

but maybe you should drive safer?

bigblack06

iTrader: (20)

Yeah that sounds terrible, in the 4GS forum someone had the same issue and he doesn't use it anymore. At least you can say it works as advertised.

crazych42

Well, the last thing I was going to do at that point was to make it worse by tapping the brakes!

Nice car!

crazych42

Well I wasn't exactly weaving in and out of traffic, but I did say the PCS did it's job and I took full responsibility for what happened.

The point is that regardless of how safe you drive, without an active steering system like Mercedes distronic plus that will possibly prevent this type scenario, the PCS COULD get you in trouble if you are trying to take evasive steering action to PREVENT an accident.

crazych42

Thanks. I'm pretty sure they were not happy with me and I wasn't going to hang around and find out. To be honest, I don't even know how to disable the PCS. I'll have to look in the manual. It's doubtful that it is something you can or would want to disable on the fly. I would either have it on and just be more aware of its capabilities/limitations or disable it all together. It's only engaged once in two months of driving and not exactly when I wanted it to...

Joeb427

iTrader: (1)

Can adaptive cruise be on with PCS off?
Or do both have to be on or off?

jhs82

I still never had my PCS to engage. Just warnings. But it's not made for that kind of aggressive driving.

There is a button to switch it off underneath the steering wheel, close to the TPMS-button.

jhs82

Two individual systems working independently.

Joeb427

iTrader: (1)

That's good because if I get the options in my next car,PCS will be turned off.
Thanks.

AdvanSLF

You're right about them effing VA drivers.. effing all a pain in my A$$!!!! i commute about 3 hours a day round trip and i swear i'll have a heart attack one of these days from so man damn dumba$$ va drivers on the road (slow int he left lane, cutting in front of you then going slow, leaving 3 or more car lengths in between them to the car in front..it just goes on)

oh yeah.. back to PCS, thats the exact thing my wife said (the scenario) during the time we purchased the car.. we opted NOT to get PCS for that exact reason!!!!!!!! glad i don't have that stupid crap! i swear it will cause more hazards then help! can't you turn it off btw like BSM?