CM2350 Active 1894 Code

[ThomasTowing]

First things first i have searched and followed and gone through this forum of vast knowlegdge about this topic before posting and theres alot of smart people in here. alot smarter than i am.. im very appreactive of the forthcoming of information people have provided.. back story on this truck is we got it already demandated, its a 2016 Intl Lonestart with a X15 that the computer says is on a CM2350. We have not had the truck long, maby a year but have only put like 2500 miles on it.. when we received it we were told it was inframed right before we received it and demandated at that time.. it has roughly 3k on the rebuild/demandate. Its a backup truck for us so its not a necessity.. now here comes the issues...

Check engine light came on with a Active 1894 code... i could clear the code and then it would come back aget about 5 min of driving.. after researching figured it was the VGT Actuator as i have had them issues on previous trucks before.. Ordered new Actuator, went to install with insite and get an active code present and then a failed install with reason 6.. though that the new actuator was bad.. had them send a second one.. did the same thing.. started reading and found to test resistance at data connector by intake. had 18ohms.. went digging through and one of the connectors where the demandated hardware was was unplugged.. jumped canbus together and then got 119 ohms at dtc.. still have active fault.. pluged original actuator in, still have active fault.. both actuators ohm out at 120.. unplugging actuator i still have 119 at dtc.. i have traced the harness from actuator up and over the trans as far as i can reach and resistance dosent come down to around the 60 mark like it should.. i have wiggled harnesses with no luck.. number stays the same..

i am at a lost as to where to go next.. so far im about 3 days into messing with this truck and lost even more now that i have the resistance i have.. please help..

[tree98]

Your likely missing a terminating resistor if someone has hacked up the original wiring to the aftertreatment components.

Look up your engine serial number on quickserve (its free) get the wiring diagram, put a terminating resistor at the 14 pin crossover connector and that will properly eliminate all the aftertreatment wiring.

I highly suggest you pull a copy of that demandate program out and have Rawze review it. There's a very high likelihood that it's extremely harmful to the engine. Rawze does this for free, there's no trickery or hidden cost for this.

[CTsolutions]

Hey, adding to what tree98 said. Ive come accross this issue at the dealer. It was a demandated truck. The vgt shares a backbone with the aftertreatment sensors. We ended up by putting a resistor at the 14pin crossover plug on the sensor side. Pins 2 and 9 if i remember correctly. Worked perfect after that.

[windowrattler]

If I'm thinking right, in your story where you jumped the can bus together you could put a resistor in there. I think one of the nox sensors down there is normally the terminating resistor.

[Rawze]

The j1939 network (under dash), and network#2 (engine wiring harness feeding vgt, egr, after-treatment components), are each supposed to have 60-ohms resistance on them. This is after the truck is switched off for at least a few minutes.

(Engine harness/ network #2) ...
The 60-ohms comes form a terminating resistor at each end of the network. They measure on their own, 120-ohms each.

Both the (120-ohm) resistors combined, when plugged in properly, makes for the 60-ohms.

== At the one end, the terminating resistor is located inside the VGT turbo controller.

== At the other end, the terminating resistor is down under the truck at either the DEF tank, or at the After-treatment components somewhere.

> BOTH ENDS of the network need a proper (120-ohm) terminating resistor for the network to function properly and have 60-ohms on it. If it is open ended (one or more terminators missing) then the whole thing is susceptible to any nearby electrical noise, and this can damage the components, especially the turbo controller.

Any noise sources like a noisy alternator, noisy inverter or APU, illegal/hi-powered CB radio nearby (or in the truck), someone passing by a radio station, passing nearby power sub-stations, etc.etc.etc. .. can damage (usually the turbo controller) + create ghost faults if the terminating resistors are not installed properly.

> The issue is that there are so many morons out there doing 'deletes' who do bad things to these trucks. Too many people are beyond clueless, and create problems like these. It is not uncommon for some complete dumbarsse to unplug all the after-treatment wiring, etc. and cause one of the terminating resistors to also get unplugged. Then later on, .. eventually, ... someone having a lot of ghost problems, or a fried turbo controller.


(60 ohms) ...
So... with the turbo controller unplugged, you should be getting 120-ohms on the J1939 network#2 engine harness, and with the turbo controller plugged in, you should be getting 60-ohms.

If the end under the truck is unplugged,.. and only the one in the turbo controller remains.. then it will usually be 120-ohms with the tubo plugged in and some random value with it unplugged.

In your case however, you posted that it was shorted out at the unplugged connection that some complete moron did .. so the resistance was lower?. - Hopefully you got this resolved.

The proper thing to do was to LEAVE ALL THE STUFF UNDER THE TRUCK IN PLACE, and hollow out all 3 elements properly (DOC, DPF, and SCR, all 3) to the bare outer shell metal internally, if someone is de-mandating it, but leave all the electrical plugged in.

If all the electrics are missing now, the solution is to ensure that a terminating resistor is installed at the plug under the truck where some idiot likely unplugged everything. Then to seal it all up properly against salt, weather, corrosion, etc.etc.. and this does not mean wrapping it up in electrical tape ... but silicone sealing it properly etc.. or simply to to plug it all back into the electrical components, if they are still in place.

> Get it back to 60-ohms with the turbo controller plugged in.. and it should read 120-ohms with turbo unplugged.

============
(de-mandate programming) ...

NEXT: yes,... you need to also ASAP!!!... copy that program from the ecm and e-mail it to me for a review of what someone did inside that ecm. More than 90% of all de-mandate programming is absolutely harmful to the engine, shortening its life by half or less. - it is nothing to ever take for granted, or make an assumption on. It is as important as preventing sand in your oil... and is just as dangerous, and it has noting to do whatsoever with anyone adding any power to the engine.

info for copy the program: http://rawze.com/forums/showthread.php?t...5#pid72945

[Rawze]

(05-24-2024 )ThomasTowing Wrote:  ...had 18ohms.. went digging through and one of the connectors where the demandated hardware was was unplugged.. jumped canbus together and then got 119 ohms at dtc.
...

There are multiple, and separate J1939 networks on the truck ... and none of them should just be arbitrarily 'jumpered' together.

What are you calling the 'dtc'?.. and what did you jumper?.

- If the harness for the after-treatment is still there, you should have been able to simply plug it back in, and not had to 'jumper' anything. If the harness is missing.. then you need to install a 120-ohm terminating resistor, right at the point that it got unplugged .. and not 'jumpered' it to anything.

example terminating resistor: https://amzn.to/4bRneAD

[ThomasTowing]

Well, got the resistor installed. Still did not have correct voltage. Found a broken wire just past the actuator plug. Got the actuator plugged in and had 59.9 ohms. Went to install actuator, passed.. (finally). Went to calibrate actuator and calibration fails. Come to find out. There is a crack on my actuator gear arm on the turbo.