2007 Dakota no bus
 

I started my 07 Dakota this morning and after about 2 seconds running she died instantly. Tried to restart and it wouldn't even turn over. All the lights on the gauge cluster light up as does all the back lighting on all the dials and switches as though the headlights were turned on but they're not. I'm also getting "no bus" where the odometer reading should be. After researching I've come across much info on the 2nd gen Dakota " no bus" issue but nothing on the 3rd gen trucks. Anyone know where I should start in diagnosing and resolving this?Thanks in advance

I would check your battery...I've heard the trucks do crazy things if your battery is going bad...

^^ this man speaks the truth.

It's a new battery. I just got home from work and thought i would check all connections to the PCM and try unplugging each sensor one at a time in hopes of finding a shorted sensor. I put the key to it fully expecting the same problem but to my surprise, it fired up and ran fine!! The check engine light is on and I pulled a " U 1403" code.

Any ideas what I should do first?

Disconnect the battery and leave it overnight.

U1403-IMPLAUSIBLE FUEL LEVEL SIGNAL RECEIVED
Must be a glitch. Disconnect BOTH battery cables, turn key to on position, touch battery cables to each other for a few seconds(TO EACH OTHER-NOT TO THE BATTERY). This drains entire electrical system and resets computer, beats waiting hours or overnite. Now turn key off and remove, and reconnect cables to battery. You should be good to go.

Thanks fellas.

Frank

Or, if you have access to a tuner, programmer, or scanner, just reset the error code. If not, go to a local auto parts store and borrow theirs.

I do have a scanner and cleared the code. Everything is functioning as it should for now so I just cleaned and lubricated all the sensor and PCM connectors. Hopefully this isn't the start of PCM or gauge cluster issues.

I had similar issues from time to time but it was a good while back and only in the winter. I had put in a new battery and found out the store sold me a bad one, go figure.

I can see a battery causing sensor issues because of out of range voltages but I just don't see how it would cause communication issues with the PCM. It's my understanding that the only thing that can cause a communication issue is a short either in a sensor, the gauge cluster or the PCM itself. Just in case, I'll load test my battery tonight and report back my findings.

Frank,

Glad to see everything is functioning as it should.
That code (U1403) does lead to the PCM so if it does come back, get your Dakota in to your local dealer, especially if the same code pops up.

Good luck and keep us updated!

Load tested the battery and it checked out fine. Also checked the alternator's performance in case there may be a bad phase but it checked out fine as well. I guess I'll just wait and see if it happens again and hopefully it wont be just as I'm ready to leave for work so I have time to try and chase it down. I'm actually waiting for a local dealership to find me a different vehicle so I can trade this thing in and hopefully that occurs before any others issues crop up.Thanks for everyone's input and ideas.

Frank

Frank,

Let us know what you end up getting.
Would love to see it!

I have no plans on ever buying a gas powered truck again. I just sold my 98 Cummins powered Ram (770,000 kms) and plan on trading in this headache (Dakota) for a Megacab Ram with a diesel. Buying this Dakota was a mistake, shoulda bought a diesel right from the get go.

Went out this morning, Started my truck and it stalled almost immediately. Started right back up with a check engine light. Scanned it to find code "u1403" again and also "p0129" which is low barometric pressure (map sensor). The code "u1403" may be residual because i don't recall weather I cleared it the last time it came up. I'm wondering if there is an internal short in the map sensor that may be causing my "u1403" code and my "no bus" issue. Any thoughts?