2017 Ram 2500 (6.7 Cummins) doesn’t delay start long enough for grid heater to go off even though it’s in diesel mode.

Question

My 2017 ram Cummins doesn't delay the start even in freezing cold temperatures. Everything is turned on and up-to-date. The diesel mode is turned on. Now I will say the truck doesn't have any trouble starting, but I'm worried about the long-term effects of starting it before the preheat cycle finishes.

 

I did my own tests back to back mornings and used the key one day, and the dash displayed the engine preheat countdown. The next day I watched from outside the vehicle and did the remote start and as soon as the dash lights came on the truck, it starts. It does not even display the preheat countdown on the dash when it definitely should have (30 degree ambient temps).

I see in the settings there is a "20s" option. That's all the information it gives...I'm wondering if that's a 20 second delay option? If so I think that would be enough time to pre-heat the engine..at least where I live (central NC).

Any help would be greatly appreciated.

Answer 1

What is the S/N on the back of the module?

Comments

SN: 001A07 140306

---

You have 2 options for a fixed delay that you can try in that case.

 

Firmware 0.36 is a fixed 10 second delay

Firmware 0.37 is a fixed 20 second delay but that may be to long of a wait.

 

Best Regards.

---

Can you elaborate on what you mean by "it may be too long of a delay"?

---

Well if the light goes out and the glow plugs begin to cool down then the ideal starting window has passed.

 

Unless on your truck the glow plugs just stay on indefintely even after the light goes out?

---

Cummins motors (All Ram diesels) don't utilize glow plugs they use a grid heater to heat the air before it goes into the intake manifold. Even after the truck is running it cycles on and off until The motor is at the optimum temperature that it doesn't need to heat up the air taken in from the outside.

So if I had a 20 second delay that would be enough time for it to do its pre-heat cycle.

back to my main question... so in my option menu under the D1 tab there is an option that is off but I can toggle it on that says "20s"... that's all it says though. There's no description about what it does. Is that a built-in 20 second delay? If I switch that to on and save it will that solve my issue?

---

Yes you are correct, grid heater/glow plug, basically warming the air in the intake.

 

The delay cannot be select through the options. That 20 seconds is for cranking time not delay.

 

Flashing the firmwres I mentioned will give you the delay specified.

- 0.36 is 10 seconds.

- 0.37 is 20 seconds.

---

I downgraded the firmware to version .37 and it still starts up without any delay. What next?

---

I can see the history of your module (001A07 140306) You never tried firmware 0.37.

 

You tried firmware 74.37. I did not say to try this version, I said to try version 0.37.

 

Best Regards. 

---

You sir are a genius! This did the trick...20 second delay will be plenty of time on cold mornings. I really appreciate your help and I'm sorry about all the back-and-forth, but I truly am grateful.

---

Glad its working how you like.

Best Regards.

---

Can you fix the newer firmware? I was on 0.36 and had issues with can bus errors I dont understand why the newer firmware even had diesel mode