PCS Error (Pre-Collision System Error)

[willstroo]

Hi team, I went through a workshop today, who did a quick scan using the OBD port to see if the car can be tuned in Australia. After they unplugged the OBD after looking though a few things (I wasn’t watching), and I started the car the car to leave, it threw a lot of error messages, including the dreaded “Pre-Collision System” error, take to dealer etc.

We were able to clear all of the errors except this one through the TechStream / OBD. Is there any ideas why this would have happened? From a few searches (many) the only other successful solves seems to be around locating electric faults through the car, or replacing a fuse. Could this be the case here, I dont see how seeing it was working prior to the OBD scan. I have cleaned the windscreen around the camera, and also the front sensor.

I am taking it back to the same shop tomorrow who said they are going to sort it, and maybe take it to the local Toyota dealer to see if they can clear it. Fingers crossed. Anyone have a similar experience?

On a separate note, since a battery reset etc and messing around trying to fix this, my “auto hand brake” does not engage anymore when putting it into park, which is annoying, how do I turn this back on?

Thanks in advance.

 

[willstroo]

OK an update, so Lexus has gone through the car and taken the majority of errors away, including the headlight malfunction and the cruise control issues. Only outstanding issue is the PCS Error: Take back to dealer etc

On advice from Lexus we ordered and installed a new radar assembly (part number 88210-47090) and unfortunately it didn't resolve it, so I have a new unit for sale if anyone in Aus needs to buy one..

We cannot calibrate the radar, as there is a loss of communication between the car and the radar, details as attached:

So its NOT an issue between:
- Can Communication System
- Front recognition camera
- front radar assembly
- Driving Support ECU

They believe the only area it can be now is the Brake Master Cylinder (part number 47056060703), which is $4,500 AUD. Hectic. But they dont actually know, its a process of elimination, and after forking for the radar for no reason, not that keen to jump in here..

I noticed on another similar thread on Mud someone had damaged the ABS speed sensor, and replacing that solved a similar issue. Considering the links to the brake cylinder as above could this be a better place to start do you think?

Please fire any advice across to me which you can. There was no impact, and nothing changed on the car other than plugging in the OBD to a laptop.

 

[willstroo]

Thinking on this further, when the tech was initially checking the OBD etc, we noticed that the wiring to the radar etc was “taught” where it shouldn’t be, routed incorrectly, and there was one clip which wasn’t plugged in.

This could be likely be a wiring issue, going into or out of the clips / modules, all it would take is one bad wire or connection.

There was no incident, no impact, for something to fail. So to me it has to be wiring to stop the communication.

 

[camino70]

Thinking on this further, when the tech was initially checking the OBD etc, we noticed that the wiring to the radar etc was “taught” where it shouldn’t be, routed incorrectly, and there was one clip which wasn’t plugged in.

This could be likely be a wiring issue, going into or out of the clips / modules, all it would take is one bad wire or connection.

There was no incident, no impact, for something to fail. So to me it has to be wiring to stop the communication.

Any news on this?

 

[willstroo]

Kind of, I took it to a local Lexus enthusiast / workshop, more of a performance shop. But his knowledge is massive on Lexus in general and we did some trouble shooting. We think and hope that it is the PCS ECU module, behind the glovebox which may have been fried. The car cannot seem to communicate with this part.

This part number: 88150-60051

I got one from a wrecker for $150, and next time i am able we will install to see if it gets rid of the error. To me it makes sense to try this rather than commit to a new brake / ABS assembly which will be a $6k shot in the dark.

Will update when i know more.

 

[willstroo]

Soooo the PCS ECU didn’t fix the error, the sage continues..