CEM -6C49 - 2004 Volvo V70

You also have a steering column module that communicates desired lighting configurations to the central electric module which then in turn closes the highbeam relay to turn on the high beams. Beings your other steering wheel buttons work, i would guess that the communication between the moduel and the CEM is ok. That leaves us with the wiring between the switch and the steering wheel module, the high beam relay, or the CEM as being the culprit. You could take out the high beam relay. Unfortunatly, the relay is integrated into the CEM, so if the relay went bad, you now need a replacement CEM. Checking the steering wheel module may be possible using a scan tool- there you could verify that it is seeing the input from the highbeam switch and you could rule in or out the wiring between the module and the switch

Under the hood there should be a box with all the relays in it .

if i remember correctly CEM contains information about immobiliser. You need to sync it with your keys at dealers.

The fuse is located on the CEM. To get to it you will need to get under the passenger side dash. Under the dash there is going to be a cloth like cover. You will need to press up on the center of the 2 clips holding the cover. Once you have the cover removed you will be able to see the CEM. To get the CEM down you need to twist the 2 tabs that are holding it up. Once you got those off the CEM should drop down just a bit and you will be able to pull it down to expose the fuses. If my memory serves me right it should be fuse #45 and it is a 15 amp fuse.

CEM also needs to be reprogrammed.

As before

For your brake lights...First check your fuses...next check your brake light switch..that would get your brakes lights working..Now cem control unit??? Do you mean (Climate Control Unit)??

its a networked car. that is one module relays info to the next. the chain is broken with it unplugged

Check the passenger foot area. The CEM is located there and many time passengers unplug connections with their feet unknowingly.

There is only thin insulation between the foot area and the CEM.

CEM= Central electronics module.

could be the CEM which is the main computer in the whole car. or it could be a communication fault in the CAN network