Attention: TDR Forum Junkies 
TDRComm
Staff Member
View attachment RamDTCs-2015.pdf
How do I start this story?
Let’s take a short look at our truck’s 20+ year evolution. How many electrical controls were on a First Generation Turbo Diesel? Answer: none. If I’m not mistaken, we didn’t see on board diagnostic (OBD) plug-in ports until the Second Generation trucks in 1996. (Or, was it 1998.5?) Regardless, today’s truck owner and service technician would be lost without code-this-that-or-the-other.
How do you read these diagnostic trouble codes (DTCs)? What do all of the codes mean? How does one determine the severity of the code? How many codes does a Ram service technician have to deal With? How do you access and read the codes?
Great questions. To answer them I went to the TDR’s web site and in the Member’s Area I clicked on Buyer’s Guide. Then, starting on page 300 and continuing for 8 pages, there is an article titled “DTCs and You.” The article was authored by yours truly; the TDR’s Joe Donnelly and John Holmes; and television celebrity/TDR writer/ASME mechanic/lots of other titles (ask his wife Diana) Sam Memmolo.
Close reading of “DTCs and You” (see next page) will answer all of the above questions. Well, it will answer almost all of your questions. I say “answer almost all of your questions” because there are questions you don’t know enough, to know enough, to ask.
Did you follow that?
The point of this rambling: In late 2014 TDR writer Joe Donnelly sourced 25 additional pages of diagnostic trouble codes that are used in your Fourth Generation (2010-current) Ram truck.
So, just like the evolution from zero codes in 1996 to the two pages of codes found in the Buyer’s Guide article, we now have 25 pages of codes that a Ram technician can source on his diagnostic equipment.
In John Holmes’ portion of the Buyer’s Guide article (again, see next page) he covers the all-too-familiar “P” codes (powertrain) and he mentions “B” codes (body), “C” codes (chassis). Back then we only focused on the P codes. Joe Donnelly’s 25 page update gives us P, B and C codes as well as listings for “U,” which deal with diagnostics with the truck’s body control module/communications center. ( Think anything from stereo speakers, to curtain air bag deployment, to “Frontal Squibs.”)
If in need, I hope you take full advantage of this resource. I’m thankful that we have this data available for you. Thanks, TDR members and writers!
Robert Patton
TDR Staff
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