Hi all, I wanted to run something by the forum. I noticed a few days ago that my Ram would not shift into 4wd (hi or lo). I did some preliminary searches but have not looked into it in-depth. Then yesterday, I cranked the truck up and received a check engine light. Checking the odometer code I noticed a P 0204. I took the truck to the dealer, who told me that the some of the injector wiring had been chewed, and that it needed replacement. ($180/Parts+labor). I received another call today stating that likely as a result of this the PCM had been shorted and needed replacement ($668/Parts+Labor). Although I'm not crazy about the prices, I need it working, so I asked that they proceed. Which brings me to the main question.

What is the possbility that this could have had something to do with the 4WD malfunction. Anything? Or am I just getting my hopes up?

 

Not related.

Your four wheel drive issues are more than likely vacuum related. When you put the truck in 4 lo, did it actually do the lower gearing, and just no 4x4 indicator light?

 

I'm not sure if it's the bulb or what-have-you, but I don't recollect ever actually seeing a 4wd indicator light work on this truck.

What I can say is that it seems like it shifts into 4 same as it always did, even a little gear grinding from time to time, it just never engages.

 

On these trucks, usually if the 4WD bulb isn't lit, the front axle isn't actually locking into the system. Rarely does the bulb go out.

 

... any advice on how/where to start to narrow this problem down (tomorrow when I get my truck back hopefully)?

 

FWIW my 4x4 works fine, but the light does not come on. Either burnt out or problem with whatever turns the light on, never cared much to check.

 

That's why I said usually. Since most of the problems we get on here the bulb works, and it's just a vacuum issue.

 

Either way, anyone have any advice on maybe troubleshooting the problem with the vacuum system? Light or no light, I can tell whether or not it works. I'll save that pesky issue for after I get the 'big stuff' knocked out.

Thanks again for everyones help!

 

Start engine. Pull connector off of cad on passenger side of front axle. (goes to the actuator, backside of axle, it should be easy to find.) Should have vacuum on the outboard port. Shift t-case into 4hi, should have vacuum on inboard port. If you don't have vacuum on either side, check source. Passenger side of intake manifold. I think it's a white line that goes to the vacuum switch on t-case.

 

Whatever varmint chewed up your wiring likely chewed on the vacuum line(s), too. Trace them and fix the leaks..