DD15 Injector Needle Codes

One of my customers has his truck at a Freightliner repair shop with codes for Injector Needle on 5 and 6. Freightliner wants to replace the injectors (all of them) and the harnesses. From what I can read online this issue is usually not injector or harness related but a MCM issue. Is anyone on here familiar with this issue?

 

I think I've had something similar before. If possible, start with the harness and see what happens.

 

Could be the harness. Even if # 5 and 6 injectors were bad, why would you replace all of them, if the other 4 are ok?

 

No not exactly. I am familiar with we believe and this is what we want to do. Ok that and you just authorized the work and financial responsibility. If that did not fix the problem you move on to the next we believe. Saw $25,000 and 6 weeks spent on a 14L Century with that program.
I was told of another 14L that went through a similar deal. Replacing all the injectors fixed that. It was under warranty and the work was done as advised. Most everything else was replaced first.
So will this fix the problem? Then maybe Ok it.
I have read that wiring harnesses should be replaced on high mileage trucks as regular maintenance. That was against my thanking but now agree with that. Faulty injector harness causes voltage spikes and hits the ECM. What is the interval for that? 800,000 or 1.5 million miles?
Changing the harness first, as mentioned, would probably not be a bad idea but is that the problem.
It has been a long time since 12.7,s were around here. We did not have much diag equipment and experience with them. Started sending problem trucks to Williams in Columbia SC. You already know they are the Detroit Diesel Distributor and we had favorable results back then.

 

I found this just now while reading up. Looks like we need to find out which MCM is on the truck. Someone said online that the new MCM has diodes to protect it. https://f01.justanswer.com/HeavyEquipmentTech/4fbc6dd6-6ce1-4603-9237-b0b4bf3ca65a_904-15.pdf

 

Thanks. A lot of us will be interested to know what you find.

 

Well I made some calls yesterday to the local Detroit Dealer (WW Williams) and they said that while they had never seen more than one injector go bad on the DD15 at one time that usually the harness goes bad and that the injector is the cause of that. He also said that it is best to go ahead and do them all because they usually chain react. I asked about the MCM and he said it could be the problem but he doubted it. I informed the customer and they forwarded my information to Freightliner dealer and they said that the tech had checked everything over and confirmed that the harness and injectors were bad. So not sure what the customer is going to do. Sometimes they just junk a truck if the bill is too high. I asked for them to let me know and I will try to keep up with it.

 

50% injector issue, 50% mcm/wiring issue. Troubleshoot it with DL, for exact logged code.

 

Surprised you got that much information from them over the phone. Thanks for the reply.
The world we live in has less people like you everyday. I will not talk about the 14L but will share about a F150 at Mark McLarty Ford in Little Rock.
College boy was working an internship in his fifth year on college. I was working a plant shut down for a past employer. The money was good for me but limited phone time. I won't stretch it all out but they said it needed a tune up. Wife got me on the phone. Yes I am sure it does. OK. The bill was $1500.00 for a college kid with gold card. A week later it was doing the same thing.
That smart mouth service writer, Adam Allen or Arien maybe, made me so mad I took off at lunch and bought a used car. Picked it up after work and loaded it on a 25 ft flatbed and was in Little Rock the next morning. Mr smart mouth was gone to lunch. Probably a good thing.
After $1500 you are now going to put your best technician on it? You believe it is a bad camshaft and replace it for 1300. Well what would it cost you to know? $300. Well I have to thank about that. Then the smart mouth and if we are not going to fix it he has to turn the rental car in right now came in.
When I started the F150 to load it on the trailer it sounded like a box of hammers. College boy: Did it sound like this the first time you brought it in? Yes. It has sounded like that for quite awhile.
Electronics are more difficult but it is a shame for the lack of qualified help.
Best of luck and let us know what you find.
Vented out but I am real slow on the OK anymore.
Best of luck there and hope they appreciate what you are doing for them.

 

Injector is causing harness to go bad ?? .... bs...not true. If your engine has updated injectors harness just troubleshoot it. If its ok font change it.
If you still have original injectors with brass cavities you will need to change them. Updated injectors have stainless steel injectors.