ACC & RDM problem

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ET4595

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Changed my rear brakes without difficulty ( pads, rotors, and clips). Yes wound back the electric safety brake (manually) and compressed the piston without any problems.

Now I have "Adaptive Cruise Control Problem" and "Road Departure Mitigation Problem" lit up on the screen when I start the car.

Tried rebooting the head unit, disconnecting the 12 V battery (yes tested voltage on the battery seems nominal and well above 12 V) .

Brakes work fine ( parking brake too). Can't reset this message. (No windshield debris issues to block the camera or the radar sensor) The scan tool shows no DTC codes.

Anybody have any thoughts???

p.s. I've had lots of trouble with the local dealerships over the years and they appear to be clueless about the Clarity in particular, so I don't have much faith in asking them.
 
I don't have any direct experience, but was surfing around looking for ideas.

It seems that vehicles with electronic parking brakes (EPB) usually have a "service mode" which fully retracts the parking brake allowing easier pad replacement. I know you said that you manually retracted the EPB. I think manual retraction is possible (with a little more time and effort), but perhaps the system now thinks that the EPB needs to be calibrated. Calibration may also require a more specialized scan tool than the one that you have. I assume you cycled the parking brake multiple times - I read that sometimes cycling the EPB can calibrate it.

I know how frustrating it can be to do a job like this and feel like everything went perfectly only to find some unanticipated computer-related issue.

I wish you luck in solving this. Please keep us posted as to what you find, as your experience can likely help others.
 
MrFixit said:
I don't have any direct experience, but was surfing around looking for ideas.
It seems that vehicles with electronic parking brakes (EPB) usually have a "service mode" which fully retracts the parking brake allowing easier pad replacement. I know you said that you manually retracted the EPB. I think manual retraction is possible (with a little more time and effort), but perhaps the system now thinks that the EPB needs to be calibrated. Calibration may also require a more specialized scan tool than the one that you have. I assume you cycled the parking brake multiple times - I read that sometimes cycling the EPB can calibrate it.
Click to expand...

The manual says to calibrate the parking brake by turning the car on, then apply and release the parking brake twice, and finally verify the red BRAKE indicator is off. It also says that an o-ring on the parking brake's actuator should be replaced when it is removed (but I find it unlikely that's the issue at hand).

Also checking the manual again, it pretty much says to check for DTC and debug based on them. While it does mention the indicated ACC/RDM errors, it doesn't have any troubleshooting steps based on the messages. Everything is based on DTC. Another possibility is malfunctioning wheel speed sensors, in addition to brake system issues, camera, seat belt buckle, and radar....

The table of problems shows no issue that would cause the amber BRAKE system warning light to be off, but the ACC warning to be on.
 
For brake fluid bleeding, some (including myself) have had to clear DTCs by OBDII scanner, after which all is well. If you are able, could try that and see if the codes are regenerated?


Sent from my iPhone using Inside EVs
 
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