CM2350 Fault Code 1683

[AlecLakeland413]

We have a 2015 prostar with intermittent derate. Code says high voltage signal to def heater valve. Valve works with direct 12v. Load tested the signal and return wires from J2 ECM plug to heater valve, both tested good. Has good heater fuse in aftertreatment fuse block. It recently also started running engine fan nonstop, the fan solenoid also test good with direct 12v. Wondering if anyone has ran into this problem caused from a different failed component. I went through the troubleshooting steps in site, including testing for continuity with any other wires in the J2 plug.

[tree98]

What is the esn and the exact code or codes you are getting?

[AlecLakeland413]

ESN-79731752 I did use quick serve this morning to find the two return wires come together for fan clutch and heater control valve. I will post what I found in the first post. Im kind of new to this ISX 15, I don't know if im on to something or not but I figured id give you what I got. Current codes I will post as soon as insite lets me back in.

[AlecLakeland413]

Active Codes-
1683 FMI 3(Aftertreatment Tank Heater Shorted to High Source)
Inactive Codes-
3714(Engine Torque Derate)
6263 FMI 3(Fan Control Circuit-Shorted to High Source)
5278 FMI 11(Def Dosing System Frozen)

[Rawze]

(12-10-2024 )AlecLakeland413 Wrote:  Active Codes-
1683 FMI 3(Aftertreatment Tank Heater Shorted to High Source)
Inactive Codes-
3714(Engine Torque Derate)
6263 FMI 3(Fan Control Circuit-Shorted to High Source)
5278 FMI 11(Def Dosing System Frozen)

He was asking for a list of the cummins faults codes, as seen in the Insite software.


==loks like its loosing the ground signal?. Maybe check wiring harnesses, or perhaps the ecm plug(s) for a bent pin?.

[AlecLakeland413]

These were straight from Insite? If im missing something let me know, like I said, Im new to ISX/Insite, but any help is appreciated. I had the whole harness that runs over the top of the transmission out, going from the heater valve to ECM no rubbed or chaffed wires anywhere. Both J1 and J2 ECM plugs I had off today and they are dry and clean, no oil, bend tabs, or corrosion. Also got a message the last time I connected Insite that popped up on the screen saying, these fault codes cannot be caused by malfunctioning ECM, def dosing unit, or def dosing valve which ive never seen before. We bought six of these trucks and I have fixed a lot of bad wires already, but not seeing that here, thus far.

[Rawze]

(12-10-2024 )AlecLakeland413 Wrote:  These were straight from Insite? ...

ok, i see it .. the 'FMI x' part was throwing it off. Alll you need is the fault code itself typically.

[tree98]

Check that line heater relay, could be stuck and letting voltage through when it shouldn't.

[AlecLakeland413]

I have swapped and replaced relays in the aftertreatment fuse/relay block behind the def tank, no change. I did keep going into the harness that runs on the driver side of block and found a broken wire, but must of had nothing to do with this problem because it still exist unfortunately.