Rawze.com: Rawze's ISX Technical Discussion and more
need new BCM? - Printable Version

+- Rawze.com: Rawze's ISX Technical Discussion and more (http://rawze.com/forums)
+-- Forum: Big Truck Technical Discussion... (/forumdisplay.php?fid=1)
+--- Forum: Ask Your question... (/forumdisplay.php?fid=45)
+--- Thread: need new BCM? (/showthread.php?tid=5724)



need new BCM? - tankeryanker - 01-22-2020

I have a 2014 Prostar with an isx 15 cummins that recently has started voltmeter randomly dropping to 0. I have discovered to get it and all my other secondary non safety electronics like power windows cruise ac etc....to start working again i have to disconnect batteries and reconnect them to get everything working again. Any thoughts or help or advice on this would be helpfull.
thx
and god bless all


RE: need new BCM? - Waterloo - 01-22-2020

My experience, when the volt meter starts acting up, going to zero or spiking, it has always been a failed alternator. I just installed another one here not long ago. They seem to be a replace every two year item anymore.

To note, the ProStar has two different amperage alternators that it uses. Certain models of the ProStar require the high voltage model, others like mine, can get away with a standard voltage unit. Check the alternator against your vin # to make sure you have the correct alternator installed.

Also, how old are the batteries? Any bulging? Same with batteries, getting to be junk along with the alternators.


RE: need new BCM? - DVT873 - 01-22-2020

Check the wiring at the starter where the battery cable attaches. It is used as a main junction point. You need to take the nut off to be sure everything is good. The ring terminals can rot. They will look good visually. Cleaning the threads off with a wire brush first will help with removal. Had one a where the volt gauge was going crazy including alarm and red light and the truck, used on short hauls was getting hard to start. Engine running voltage at the batts was 12.3 or so. At the alt it was about 14.6. Nut was loose on the starter. Alt output wire goes directly there and then to the batts. Ignition switch feed also comes from down there. Odd thing was there were no codes in Diamond Logic or Insite. Note, If anybody ever needs to replace any wires down there they are fusible links for about 6 to 8 inches up from the starter. Usually just the terminals. Could still be an Alt but with your other problems I would start there.


RE: need new BCM? - Rawze - 01-23-2020

could also be the cab fuses acting up... they are notorious for causing ghost problems like this...
http://rawze.com/forums/showthread.php?tid=1514&pid=12861#pid12861