Check engine light and Econ light not coming on

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

miles01

Senior Member
Joined
Sep 27, 2020
Posts
124
Reaction score
77
Location
Alberta
Ram Year
2018
Engine
6.4
The check engine light all of a sudden came on and the ecno light is not coming on as well as MDS is not working today. The truck still drives normal with no miss and performance is as good as it always was, with the same mileage according to the evic.
I can tell when the MDS was working on my truck because I can hear it and feel the vibrations as well as the difference in power. It does transition into and out of the MDS very smoothly and quietly but I do notice the difference. The only time it worked before was in city driving with very light peddle or on the height going 100kmh or less on very flat or down hill and no head wind.
Truck is a 2018, 2500 with 3.73 gears, 6 speed transmission, crew cab Laramie, with rambox.
Does anyone know what the problem might be.
 

olyelr

Senior Member
Joined
Nov 18, 2018
Posts
4,674
Reaction score
3,419
Location
Kewadin MI
Ram Year
2016
Engine
6.4
Just go get the code scanned and it will tell you.

I find it funny, though...my half ton is throwing a code for a failed fuel sensor (damn red squirrel has chewed on the wires going to it on top of the tank), and ever since then the MDS no longer works now. Makes no sense to me why they would program that to happen just because there is a code popping up.
 

2003F350

Senior Member
Joined
Feb 23, 2013
Posts
1,226
Reaction score
1,130
Location
Michigan
Ram Year
2022
Engine
6.7 CTD
They do it in an attempt to cut their own liability. I have no idea with OP's issue, we need to know what code it's throwing, but your fuel sensor could possibly some way maybe in a round about way cause issues with low fueling, and running the MDS lean could lead to a destroyed engine. If that happens under warranty then they're paying for a $4k engine install.
 

MADDOG

Not RamForum Staff
Supporting Member
Military
Joined
Dec 26, 2011
Posts
14,443
Reaction score
9,877
Location
Arizona
Go get your code(s) read and list them here.
 

NewBlackDak

Senior Member
Joined
Feb 9, 2014
Posts
1,083
Reaction score
654
Ram Year
2014
Engine
Hemi 6.4L
AutoZone reads codes for free. You have to start there with all the computers control and sensors


Sent from my iPhone using Tapatalk
 
OP
OP
M

miles01

Senior Member
Joined
Sep 27, 2020
Posts
124
Reaction score
77
Location
Alberta
Ram Year
2018
Engine
6.4
New motor in Canada is $12k at motor shop, $15k dealer.
No Autozone in Alberta Canada.

I disconnected the negative battery cable for about 15-20 mins. Reconnected, the check engine light is now off, no messages, and ecno/MDS is working again.
But no satellite radio only FM and AM radio shows up!!WTF.
Repeated battery disconnect / reconnect, all good again.
Only had the reset my Apps on the screen to where I had them before and change the theme back to my preferred colour.
 
OP
OP
M

miles01

Senior Member
Joined
Sep 27, 2020
Posts
124
Reaction score
77
Location
Alberta
Ram Year
2018
Engine
6.4
It’s been almost two weeks and no issues, no check engine light, no messages, eco light and MDS working fine, and satellite radio working.

I don’t know why it happened, and it only happened once, must have been a computer clich.
 

JohnnyMac

There are no stupid questions, just stupid people.
Military
Joined
Mar 31, 2018
Posts
2,558
Reaction score
2,920
Location
SouthWest Washington
Ram Year
2018 1500 Laramie
Engine
3.0 EcoBurner
Glad it's fixed and thanks for coming back with what you did. Hopefully it'll help someone else down the road.
 

NewBlackDak

Senior Member
Joined
Feb 9, 2014
Posts
1,083
Reaction score
654
Ram Year
2014
Engine
Hemi 6.4L
If it keeps happening, and coming back in shorter and shorter intervals until you finally can’t reset it…
Mine did that. It was a $14 purge canister. Took 10 minutes to install.


Sent from my iPhone using Tapatalk
 
OP
OP
M

miles01

Senior Member
Joined
Sep 27, 2020
Posts
124
Reaction score
77
Location
Alberta
Ram Year
2018
Engine
6.4
If it keeps happening, and coming back in shorter and shorter intervals until you finally can’t reset it…
Mine did that. It was a $14 purge canister. Took 10 minutes to install.

what is a purge canister
Pics and location please
 

2021ramlar1500

Junior Member
Joined
Nov 19, 2020
Posts
2
Reaction score
1
Location
Lancaster
Ram Year
2021
Engine
Hemi5.7etorque
what is a purge canister
Pics and location please
It’s been almost two weeks and no issues, no check engine light, no messages, eco light and MDS working fine, and satellite radio working.

I don’t know why it happened, and it only happened once, must have been a computer clich.
 

2021ramlar1500

Junior Member
Joined
Nov 19, 2020
Posts
2
Reaction score
1
Location
Lancaster
Ram Year
2021
Engine
Hemi5.7etorque
Waiting for delivery of our 1500 Hemi 5.7 L etorque. But we’ve had this problem in our Honda V6 minivan with variable cylinder management. It also shows an Econ light when active and you can feel it Deactivate cylinders although ever so slightly.
So pretty similar technology and for us it was an exhaust oxygen sensor needing replacement. It was also very intermittent at first.
If you live in a remote location it might be worth buying a $40 computer diagnostic handheld device from Amazon. Mine has really come in handy for what seems like the fleet of vehicles I help manage with my college kids
:)
 

Latest posts

Forum statistics

Threads
194,926
Posts
2,864,176
Members
155,296
Latest member
VLG6963
Top