I have a 2009 laramie 4x4. I just put a remanufactured 5.7 hemi in it. When the shop gave it back after installing the new motor the check engine light popped on for a MDS solenoid. The mechanics ended up putting in new MDS solenoids. The truck ran fine for about 60miles and then check engine light popped up again for the same problem. And now I can't remotely start it either. Has anyone one ever come across this and is there something that can be causing this. I have also put a new 800cca battery in thinking maybe a voltage problem but still same thing. So please help what else should I do. Maybe a new MDS wiring harness?

 

09 is a fourth gen truck. Moving this to fourth gen section for ya.

Welcome to DF!

 

Thank you.

 

I'd check the MDS harness from each solenoid to the main harness/PCM. In fact I would check ANY wiring that would have been disturbed during the process.

 

Would you know of a place that would sell a replacement wiring harness. Dodge has discontinued it.