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-   -   Volvo S80 c.e.m. (https://volvoforums.com/forum/volvo-s80-18/volvo-s80-c-e-m-108353/)

Paul Guthrie Dec 6, 2021 01:38 PM

Volvo S80 c.e.m.
 
What will cause a c.e.m. to get hot at the fuel pump relay enough to turn it black? Also where would be the best place to get a cem pre programed for the car I so believe it is fried due to the immobilizer message on dash and the no starts at times unless I unplug and replug the fuel pump relay in or move the c.e.m. module around.?
https://cimg2.ibsrv.net/gimg/volvofo...8e50424044.jpg
https://cimg3.ibsrv.net/gimg/volvofo...67dc1b8db9.jpg

hoonk Dec 6, 2021 02:19 PM

Try xemodex.com for a preprogrammed module. And either a poor connection or high current flow caused the melting - now there is probably a really poor connection which will generate more heat.

Paul Guthrie Dec 6, 2021 08:46 PM


Originally Posted by hoonk (Post 505480)
Try xemodex.com for a preprogrammed module. And either a poor connection or high current flow caused the melting - now there is probably a really poor connection which will generate more heat.

Thank you, yea found xemodex awhile back there pretty cheap compared to the dealers, and you have to send the old one in with the ecm and key to get a preprogrammed one. An I just replaced the fuel pump the gauge would read wrong at times so I don't know if that was the cause or what.

mt6127 Dec 7, 2021 08:28 AM

sometimes when fuel pumps go bad they start to draw too much current (which in turn fries the relay). that would explain the browning and in turn create a poor connection which as hoonk noted will create more heat. You can try cleaning up all the contacts to see if that helps. Another site to check out for rebuilding CEMs is Midwest ABS.

Paul Guthrie Dec 9, 2021 05:26 PM


Originally Posted by mt6127 (Post 505514)
sometimes when fuel pumps go bad they start to draw too much current (which in turn fries the relay). that would explain the browning and in turn create a poor connection which as hoonk noted will create more heat. You can try cleaning up all the contacts to see if that helps. Another site to check out for rebuilding CEMs is Midwest ABS.

I'm pretty sure the c.e.m. board is fried, between the immobilizer message on dash and having a no start issue plus last time I scanned it with a good scanner I believe it had codes in there saying lost communication with fuel pump, tcm, and ecm. Starting to think when I first bought this thing I never needed to do the etm rebuild for the TPS side because it still does wierd stuff with transmission after 40 mph.


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