DDEC comes on unreliably

[chessie4905]

that manual on ebay will give you the basics on exactly how these computer systems work. particular engine sensors won't be identical, but their function and testing is still the same to current systems. This will take away the mystery of engine control systems in easily understandable language.

[Sebulba]

that manual on ebay will give you the basics on exactly how these computer systems work. particular engine sensors won't be identical, but their function and testing is still the same to current systems. This will take away the mystery of engine control systems in easily understandable language.

Thank you

Seb

[Sebulba]

like GM products, many times a fault will trigger multible codes because the ground or voltage feed is interconnected. wires going from front to back can be checked by disconnecting plugs or connectors at both ends and using a wire tracer to verify correct wire. then wire checked for resistance. Most computer circuits are fed 5 volts and the return wire voltage or resistance is read by computer to be in a specified range. Each component in a Computer system is expected to be in a certain range when engine is operating. Find a GM computer command control diagnostic manual from Oldsmobile, for example. It explains how computer command control (ccc) works for each component. Basically what they used in DDA engines till they started using frequencies on the same wire in the latest computer systems. This is a manual everyone should obtain to make your life easier if your coach has a computer.
https://www.ebay.com/itm/403802509970?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=4TOpVwFhTEa&sssrc=2349624&ssuid=QbPh_E0WTG6&var=&widget_ver=artemis&media=MORE

I just bought that book, Thanks for the suggestion.

Seb

[chessie4905]

The big difference since the early 80's, is how to go about the diagnosis. Started out using a VOM. (volt,amp,ohm multimeter) to do measurements. As years progressed they came up with scan tools that did the diagnostic work, saving a lot of time. For a decent technician, that is. For a clueless inexperienced tech, just swapping parts without sucessful repair is the result. A dealership is only going to pay good income for one, maybe two good techs. They dont want to pay higher salaries for basic repairs and oil change employees.
That manual will help remove the mysteries of these systems.

[luvrbus]

The student hand book for the DDEC is simple if you can find one,I used to let people use mine  too make copies I started with 6 and now I only have 1 left since people would never return the manuals, I have the Allison application manual too I let people make copies of and it has always been returned 

[Van]

https://silverleafelectronics.com//?page_id=2434

[Sebulba]

The student hand book for the DDEC is simple if you can find one,I used to let people use mine  too make copies I started with 6 and now I only have 1 left since people would never return the manuals, I have the Allison application manual too I let people make copies of and it has always been returned

Perfect, I'm looking forward to digging into it.

Thanks

Seb

[Glennman]

I know this is another person's thread, but without knowing much of what a DDEC is, I believe someone said somewhere that they stopped using them in 2002(?). My bus is a 2002 MCI D4500 12.7 Series 60/B500. How would I know if I have the DDEC or whatever other thing replaced the DDEC?

[Bill Gerrie]

DDEC was in use in 2002 for sure. It probably DDEC IV. A Prolink will tell you what version you have.

[chessie4905]

https://www.google.com/url?sa=t&source=web&rct=j&url=https://dieselengineparts.highwayandheavyparts.com/blog/detroit-diesel-ecus-explained%3Fhs_amp%3Dtrue&ved=2ahUKEwjC17mQt6n6AhX7D1kFHbBfC2EQFnoECBwQAQ&usg=AOvVaw2AdpjhClBdPwRyIeD_SFi8

[luvrbus]

The DDEC is alive and well only the 60 series for highway use went away when M/B introduced the DD13 in 2011, the 60 series is still made for marine and industrial use, it owned by BMW now 

[Glennman]

Nice (sorry for stealing your thread Sulbulba!). I thought the model of Pro-Link a person bought had to be specific to which system you had.

[Bill Gerrie]

The Prolink is universal. It is the card you put into it that is specific to a certain engine.

[Sebulba]

Nice (sorry for stealing your thread Sulbulba!). I thought the model of Pro-Link a person bought had to be specific to which system you had.

You're fine.  We're all trying to learn this stuff.

Seb

[Sebulba]

Hello all,

Short update.  Since waiting for the lights to out have had no issues.  We went from Yellowstone to Rapid City, SD with one stop in Pierre, SD Walmart for the night. Then on to Minnesota and now in Enid, OK with a few more stops between.

Thanks for the help

Seb