GR Yaris Pre Collision System malfunction after alignment

[chewlo]

Hi all,

I've encountered the PCS error as in the title after an alignment. Is there a quick way to fix this? Unfortunately I didn't take note of the error code, however the message says
"Pre-collision system malfunction. Visit your dealer immediately"

I have seen elsewhere that the system can recalibrate itself after some time, but I'm not patient
Ive also seen that you can clear this via Techstream, but I'm not willing to pay for the package.

Hopefully someone can share a quick fix.

Thanks

 

[TheManWithTheStick]

I've had this a couple of times but it cleared itself. Have you checked for dirt or something on your front camera (top middle of windscreen) and the radar sensor? Could just be that.

 

[Humptydumptyhadabigone]

You haven't disconnected the radar unit for any reason?

 

[chewlo]

I've had this a couple of times but it cleared itself. Have you checked for dirt or something on your front camera (top middle of windscreen) and the radar sensor? Could just be that.

Yeah gave it a clean - usually I just need to unplug/reconnect the battery and it's all cleared after

You haven't disconnected the radar unit for any reason?

Nope - only thing I can think of is I may have pulled on the ABS wiring when installing coilovers over the weekend. Will give them a look when I can

 

[Onehp]

Drive straight for extended time seemed to help mine but it took a few days.

 

[Humptydumptyhadabigone]

Error code would narrow it down.

 

[JJT]

Yeah gave it a clean - usually I just need to unplug/reconnect the battery and it's all cleared after


Nope - only thing I can think of is I may have pulled on the ABS wiring when installing coilovers over the weekend. Will give them a look when I can

In the end, what was the problem?

 

[chewlo]

In the end, what was the problem?

Something in the brake module within the cars' software.

Tried to clear it myself with Techstream, but I must've gotten the wrong cable or version since it wouldn't connect properly. That's what I get for getting some dodgy cable off eBay, I suppose.

Either way, sent it to the professionals aka my tuner/mechanic and they cleared code the code relatively easily via Techstream. Unfortunately, I didn't get the actual error code off them.

 

[Garby]

Just installed my shockworks coilovers in the front and have the same issue. To be fair I had -5 degrees of neg camber FR and just went for a 200 metre drive to let it settle for height check.
I have since got both F & R to ~-2 degrees.

I am seeing on a dodgy techstream

System: Lane Control
Code X2003 Brake Control System Malfunction

When I clear it is comes straight back so probably not the root cause but might help. I haven't gone for much of a drive yet so see it if self corrects yet. It did steer left quite hard when it initially gave the error so I understand why it freaked out, but is driving straight now. I still have the rear coilovers to go on, then new wheels, tyres, so no point trying to fix it too much just yet in case it comes straight back.

 

[cdruk]

I had this problem on my gen 2 after installing camber bolts. You need to clear it with tech stream. I ordered cable and software off Ali express for about 13€. You can tell techstream it’s a gen 1 and it works fine (techstream doesn’t know what a gen 2 is).

Anyway, it is not enough to clear the error codes, you need to clear the Vehicle Control History (RoB) entries for all modules concerned. Otherwise the error code will keep coming back.

Here is a picture of my techstream view for one of the modules before clearing the RoBs:

Hope this helps!

 

[Garby]

Thanks @cdruk

Still learning Techstream - you got me sorted - thanks! Yeah makes perfect sense that it looks back on previous data and determines nobody has cleared/fixed this and errors again.