07-29-2012, 01:07 PM
hi,
i thought i would share my recent experience with a DDEC4 error code. a few months ago i started getting PID103. Turbo Boost Circuit Voltage Low error code on my Prodriver and if i had my VMSPc hooked up it was there too.
it would sometimes go out after a restart and other times not. it also gave a yellow check engine light on my coach.
the first time i drove it with the error active i got about a mile and the stop engine light came on and the engine de-rated. i pulled over and restarted the engine and it cleared up and didnt come back that short trip.
this intermittant nature continued. i bought a turbo boost sensor and replaced it as it is very easy to get at and change. no improvement.
the one i bought was for 15 bucks used on ebay. so my bus shop said to try a new one. 65 bucks and no change.
i drove it to my bus shop and of course once i got there it didnt do it even though it did it all the way there. they could see the code in the DDEC with their scanner.
they checked the wiring as that is the most common problem for this code. it was all fine. the DDEC4 ECU is just a foot below the sensor so the wiring harness is all just right there.
so, my bus shop had the local detroit shop put it on a dyno and they could not duplicate it at all.
that was the day before our big trip we just returned from.
so, the first 1200 miles, no problem. we were at newell in miami and they were all leaving for the day and they were just finishing pressure washing my radiator and they did the engine too. as soon as i started it, the same code came up. aha, it must be related to being wet...
so i drove with the code on all the way to central diesel repair in springfiled MO, getting there about 830pm on the 3rd of july. they got me in right away and a very very experience detroit mechanic got going. he first thing took the DDEC4 unit off of the engine. as he did, a bolt fell from behind the unit that was wedged between it and the block. it was not part of the mounting for the DDEC. the DDEC is electrically isloated from the block with rubber grommetts.
the back of the DDEC has started to wear from the vibration of the bolt, but thankfully not all the way through.
as soon as he took it off completely, we looked at the pins. he said that was the only way to reallyget a good look at all the pins. sure enough, on the plug that the turbo boost sensor comes in on, there was a bent pin. it was an unused pin, but it was sideways and wouldnt allow the plug to fully seat on the DDEC so that had to be an issue. and why likely when there was water something happened. the ground short caused by the random bolt could have caused something as well.
there was also a mod done on the DDEC4/series sixty that added a barometric pressure sensor directly inline with the turbo boost sensor. David Brady had told me about it before and that he had had issues after the mod was done. so we also took that out by just unplugging it. it is still there and i can plug it back in if i need too.
all i know is that in two hours, they did all that and put it back together and in many many starts and stops and rain and about 3000 miles of driving, no issue with the turbo boost code now.
lesson learned is to closely examine the pins on the DDEC unit if you are having any issues.
tom
i thought i would share my recent experience with a DDEC4 error code. a few months ago i started getting PID103. Turbo Boost Circuit Voltage Low error code on my Prodriver and if i had my VMSPc hooked up it was there too.
it would sometimes go out after a restart and other times not. it also gave a yellow check engine light on my coach.
the first time i drove it with the error active i got about a mile and the stop engine light came on and the engine de-rated. i pulled over and restarted the engine and it cleared up and didnt come back that short trip.
this intermittant nature continued. i bought a turbo boost sensor and replaced it as it is very easy to get at and change. no improvement.
the one i bought was for 15 bucks used on ebay. so my bus shop said to try a new one. 65 bucks and no change.
i drove it to my bus shop and of course once i got there it didnt do it even though it did it all the way there. they could see the code in the DDEC with their scanner.
they checked the wiring as that is the most common problem for this code. it was all fine. the DDEC4 ECU is just a foot below the sensor so the wiring harness is all just right there.
so, my bus shop had the local detroit shop put it on a dyno and they could not duplicate it at all.
that was the day before our big trip we just returned from.
so, the first 1200 miles, no problem. we were at newell in miami and they were all leaving for the day and they were just finishing pressure washing my radiator and they did the engine too. as soon as i started it, the same code came up. aha, it must be related to being wet...
so i drove with the code on all the way to central diesel repair in springfiled MO, getting there about 830pm on the 3rd of july. they got me in right away and a very very experience detroit mechanic got going. he first thing took the DDEC4 unit off of the engine. as he did, a bolt fell from behind the unit that was wedged between it and the block. it was not part of the mounting for the DDEC. the DDEC is electrically isloated from the block with rubber grommetts.
the back of the DDEC has started to wear from the vibration of the bolt, but thankfully not all the way through.
as soon as he took it off completely, we looked at the pins. he said that was the only way to reallyget a good look at all the pins. sure enough, on the plug that the turbo boost sensor comes in on, there was a bent pin. it was an unused pin, but it was sideways and wouldnt allow the plug to fully seat on the DDEC so that had to be an issue. and why likely when there was water something happened. the ground short caused by the random bolt could have caused something as well.
there was also a mod done on the DDEC4/series sixty that added a barometric pressure sensor directly inline with the turbo boost sensor. David Brady had told me about it before and that he had had issues after the mod was done. so we also took that out by just unplugging it. it is still there and i can plug it back in if i need too.
all i know is that in two hours, they did all that and put it back together and in many many starts and stops and rain and about 3000 miles of driving, no issue with the turbo boost code now.
lesson learned is to closely examine the pins on the DDEC unit if you are having any issues.
tom
2002 45'8" Newell Coach 608 Series 60 DDEC4/Allison World 6 Speed HD4000MH
