Check eng light

[DSTdriver]

Isx 2350 check eng light code 4858
What's it for
Thanks for any help

[Rawze]

my FIS says code 4858 is not found.

what kind of truck? some hsitory? etc.?

[DSTdriver]

Rechecked with code reader my bad it's spn5848

Peterbuilt 2014

I do the check on dash & it comes up connect service tool

If I cycle the key switch to off & on generally 6-8 times the light goes out for awhile but getting more frequent

Gonna try & get insite set up just not good with computer but I know this needs to happen soon

[Waterloo]

I found this... https://www.justanswer.com/medium-and-he...-code.html

Here is what it says, I will only paste the first part, follow the link for the rest...

Here is the Cummins full note on the fault so you can give to the shop and not have to go through the diagnostic fee.
Fault Code 3936
SPN 5848
FMI 12
Aftertreatment 1 SCR Intermediate NH3 Sensor- Bad Intelligent Device or Component

[DSTdriver]

(04-19-2019 )Waterloo Wrote:  I found this... https://www.justanswer.com/medium-and-he...-code.html

Here is what it says, I will only paste the first part, follow the link for the rest...

Here is the Cummins full note on the fault so you can give to the shop and not have to go through the diagnostic fee.
Fault Code 3936
SPN 5848
FMI 12
Aftertreatment 1 SCR Intermediate NH3 Sensor- Bad Intelligent Device or Component

Thanks for the help Waterloo

At least now I have a direction to go before it becomes a problem

[DSTdriver]

Replaced the NH3 probe & module everything fine for about 4 days then check light again,
Clear it goes a bit then again more of the same

Seems to be intermittent
Ran it on insite did regen
Everything checks out good

Kinda baffled

[Waterloo]

How about the SCR system filter? I hear they throw some wild codes if not changed regularly.

How many miles on the truck?

[DSTdriver]

Not sure what scr filter is
Truck has 291,000 miles
8,800. Eng hrs

[Waterloo]

You have to put DEF in the truck correct? Or has it been deleted? The DEF is fed through the SCR system, there is a filter under there somewhere near the DEF tank, that needs to be serviced now and then, I would think at least once or twice a year. If not serviced strange codes pop up and can lead to further SCR system damage if I recall correctly. I have an older truck, no SCR system, just going by what I have read here and heard at Mr Hagg's shop and Rawze's house.

If you have a delete, I am assuming you do not, and are getting this SCR code, I would say you have other, possibly more serious issues going on, and need to have the programming inspected.

I wish I could be of more help, hopefully one of the guys with SCR experience will chime in.