Dtc p3400

fire502 · #1 08-17-2009, 10:40 PM

OBDII reader says cylinder deactivation system? I checked this for a friend. He has a 2006 Ram 1500 4x4. He was driving his truck and it suddenly died on him. He thought maybe the accelator was acting up that day as well. If any of you know what might be the problem, please let me know. He isn't sure if his truck has the MDS or not. It started acting up when he had his cruise control on.

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chambers · #2 08-18-2009, 12:29 AM

That sounds like an MDS problem since MDS is cylinder deactivation. I assume his 06 is a hemi so it would have MDS, but I don't have a clue how to fix it.

fire502 · #3 08-18-2009, 02:02 PM

Thanks for the reply,,and yes it is a 5.7 Hemi....and he has no idea if it has MDS.. I would think it has some kind of indicator light or something when it is activated. I have a 2006 Mega Cab 4x4 without the MDS so I have no idea how to tell. He is taking it to the Dodge shop today,,,if they find anything out, I will post it for others to learn from his mishap!!

truckin151 · #4 08-18-2009, 02:54 PM

If its an 06' 1500 w/ Hemi it HAS the MDS, It is standard on all trucks 06+ except the 2500's and Mega cab's I believe.

fire502 · #5 08-19-2009, 11:30 AM

ok, P3400 leads us to a bad MDS solenoid, so that is solved, but where is it. I can get the part for $40, but dodge dealer wants to charge $600 to replace it. If anyone knows where it's at, please let me know!!

chambers · #6 08-19-2009, 02:24 PM

From what I can see in the manual it looks like the intake manifold has to be removed and there are several MDS solenoids. This might be a job best left to the dealer, but maybe someone on here has done it and can help you further.

fire502 · #7 08-19-2009, 04:43 PM

thanks for the help!! If I find out anymore info, I will post for the next guy with this problem.

chefred112 · #8 08-19-2009, 09:09 PM

can he drive it around now? just without mds?

chambers · #9 08-19-2009, 09:39 PM

Fred makes a good point. Why not spend a half the repair cost on a tuner and turn off MDS since from everything I've heard it doesn't help mpg that much. I would talk to a dodge mechanic first to make sure that this won't come back to bite you in the butt, but getting a tuner to "repair" the truck sounds like the better option.

chefred112 · #10 08-20-2009, 11:19 AM

i've seen the mds solenoids under the intake (during an engine swap)...an yup, right under the intake as said above...you can just take the intake off to eyeball them...