3cyl high idle Electrical bug! Bad ECM

[Mopar1973Man]

IAT temperature is key. If the IAT is <32*F it will trigger 6 CYL mode. If the IAT is <15*F then 3 CYL will start. Remember the IAT measure is while grid heaters are active so it needs to be much colder and the truck be parked outside to trigger 3CYL mode.

 

High idle will self cancel at 170*F of coolant. It's capable of restarting if the coolant falls below 140*F again then high idle with restart in the last mode of operation. 

 

P0113 is not a short but a open on the signal or ground lead. If the ECM detecting high volt code that is a open lead problem or broken wire. Typically that would be detected when you measure ohms from ECM to IAT plug it would show up as a open lead or infinite ohms. 

[JP907ATB]

Oops i meant check engine light stays off with my old Ecm after clearing codes, but i think the 3cyl high idle is engaging when it shouldn’t be 

[Mopar1973Man]

Totally based on IAT temperatures. If IAT is reporting 15F or less then 3 CYL mode will start.

[JP907ATB]

Yeah my IAT was in the 40s and 3 cyl high idle was still engaged/engaging 

[Mopar1973Man]

Something is wrong with that ECM it shouldn't be enabling high idle unless the IAT is under +15*F. Any error codes?

[JP907ATB]

Once i changed my IAT sensor connector i was able to clear the po113 high input code with no return. But my old ecm was still acting funny engaging high idle when it was to warm for it. I am thinking between the bad sensor connector and all the electrical diag i did that i damaged the ecm somewhere along the line. I put in a different ecm and i hadn’t no codes and was idling properly. My smarty would not communicate with the new ecm though, so i emailed Bob Wagner @smarty power, and he sent me a recovery software, and i successfully recovered the new ecm and smarty will now communicate. So everything appears to be functioning normal now, headaches are gone for time being. The recovery file he sent me is equivalent to a stock dealer flash and will work on 98.5-01 trucks so I’m pretty stoked on that software! Also Bob informed me that the 98.8-99 trucks had a weak flash memory in the ecms and that if i have problems with this new ecm tonfind a 00-01 ecm which have stronger flash memory to my understanding. I would like to thank you Moparman and all the other members on this forum for helping me get to the bottom of my electrical bug! Thank you! Cummins is purring like a kitten!

[Mopar1973Man]

12 minutes ago, JP907ATB said:

so i emailed Bob Wagner @smarty power, and he sent me a recovery software, and i successfully recovered the new ecm and smarty will now communicate.

 

FYI... The actual Smarty support site is SmartyResource.com. They also do VIN unlock and recovery files as well. 

https://smartyresource.com/support/

 

[dave110]

Glad you got it figured out. I have heard Bob say that before about the early ECM's and that explains to me why the majority of ECM failures I read about are on early model trucks. Was Bob saying that an 01 ECM could be flashed to work on a 98.5-99 truck?

[Smarty Support]

14 hours ago, dave110 said:

Glad you got it figured out. I have heard Bob say that before about the early ECM's and that explains to me why the majority of ECM failures I read about are on early model trucks. Was Bob saying that an 01 ECM could be flashed to work on a 98.5-99 truck?

 

It sure can. 00, 01, or 01.5 are the prefered ECM's. You can get ahold of me on our support system @ www.smartyresource.com

with the truck information and I can have my programmer build the truck specific recovery software to allow using a different ECM..

[dave110]

Thanks You! My spare ECM is from a 99 truck so it would be plug & play if I ever need it. I may look for a newer model now that I know it's possible to use.

[JP907ATB]

Quick question... if i engage my manual high idle, it’s set just about 1200rpm would it be bad to turn on me pac brake to help warm up?

[Smarty Support]

Indeed let me know Dave. On the Smarty site www.smartyresource.com

you will see the support tab so you can designate the ticket to recovery. I watch those pretty close and unless I am in the shop or in a conference I will jump right on it pretty quick..

 

Thank you!

 

Edited January 17, 2018 by BrianAtSmarty

[Mopar1973Man]

2 hours ago, JP907ATB said:

Quick question... if i engage my manual high idle, it’s set just about 1200rpm would it be bad to turn on me pac brake to help warm up?

 

6 CYL you fine go for it. 

 

3 CYL watch the EGT's it might get too hot with 3 CYL and exhaust brake on. I typically see right at 900*F on 3 CYL mode.

Edited January 17, 2018 by Mopar1973Man

[JP907ATB]

Okay thanks, yeah i haven’t unlocked 3cyl on my new ecm yet, with smarty. I’m just staying stock right now to make sure all my bugs are gone before i mess with ecm programming. And regular high idle Dosent seem to do much as far as getting up to operating temp and staying there. 

[Dieselfuture]

2 hours ago, JP907ATB said:

Quick question... if i engage my manual high idle, it’s set just about 1200rpm would it be bad to turn on me pac brake to help warm up?

You should be fine I've done it and many others, @Mopar1973Man I believe that is the idea behind it 

Edit , ignore my post my phone didn't show me all the replies right away

1 hour ago, JP907ATB said:

And regular high idle

How are you getting that to turn on, wife ecm is not enabled. With quad?

Edited January 18, 2018 by Dieselfuture

[JP907ATB]

26 minutes ago, Dieselfuture said:

You should be fine I've done it and many others, @Mopar1973Man I believe that is the idea behind it 

Edit , ignore my post my phone didn't show me all the replies right away

How are you getting that to turn on, wife ecm is not enabled. With quad?

I don’t understand what your asking?

I don’t know about quadzilla but i know with smarty if you program a tube, and then program back to stock it unlocks high idle(6cyl) and 3cyl high idle. I haven’t done that to my new ecm yet, but i have a little switch wires to a little deal under the throttle body that will hold the throttle open at set amount rpm. It is not strong enough to push the throttle by itself, so i have to flip the switch and tap the throttle and it will then Hold at 1200rpm

[Dieselfuture]

2 minutes ago, JP907ATB said:

I don’t understand what your asking?

Yeah sorry about that I'm using speak to text on my phone it's retarded, I was wondering how you turning on your high idle if your ECM is not enabled