Detroit DD16 GHG14 (2014-16) Fault Code: SPN 986 FMI 19 (CPC) Signal Source #1 or #2 is Erratic

NOTICE: This fault does not indicate a common powertrain controller (CPC) issues, do not replace the CPC.

NOTE: J1939 CM1 SPN 986 signal source #1 or #2 is erratic.

NOTE: This fault indicates that the CPC has received a J1939 CM1 message; however the “SPN 986 requested fan percent speed” is in error.

NOTE: If codes 168-0, 168-14, or 168-18 active fix those first.

NOTE: If ECM has been programmed recentely, check programming to ensure it is correct.

NOTE: This code is coming from another computer on the vehicle (ABS, Transmission, etc…).