04-14-2024, 08:04 AM
Changing the CEM is not simple. As far as I know, they are coded to the VIN and to other ECUs. So getting a used will not work without cloning your current CEM.
CEM cloning is done on the bench with special tools and software.
Connect the sensors and start the car and put the car to Drive or reverse. If there is a real error, you should see on the screen "park assist not available"
Another test is, remove all the front sensors from their connectors and check the CEM output voltage on PIN 1(+) and PIN 3 (-) on each connector. If you get negative value, that means polarity is wrong. Check for the DTCs if you get different ones or same 4.
Then Check continuity on PIN 1(+) and PIN 3 (-) on all connectors, it must be zero. (no continuity) if you have, than there is a short either on of the connectors or inside the CEM.
The final test is testing the sensors.
Put the car to reverse, go to back of the car and block the sensor with thumb, you should hear clicking noise. Do the same for the front ones.
You can also check the resistance between pin1 and pin2. It should be around 10k ohm. If you are seeing no resistance or too high, that means sensor is faulty.
CEM cloning is done on the bench with special tools and software.
Connect the sensors and start the car and put the car to Drive or reverse. If there is a real error, you should see on the screen "park assist not available"
Another test is, remove all the front sensors from their connectors and check the CEM output voltage on PIN 1(+) and PIN 3 (-) on each connector. If you get negative value, that means polarity is wrong. Check for the DTCs if you get different ones or same 4.
Then Check continuity on PIN 1(+) and PIN 3 (-) on all connectors, it must be zero. (no continuity) if you have, than there is a short either on of the connectors or inside the CEM.
The final test is testing the sensors.
Put the car to reverse, go to back of the car and block the sensor with thumb, you should hear clicking noise. Do the same for the front ones.
You can also check the resistance between pin1 and pin2. It should be around 10k ohm. If you are seeing no resistance or too high, that means sensor is faulty.