A few days ago I got some water in my gasoline. At idle it would run rough but straightened out as soon as I took off. Problem is that it set off the "Check Wallet" light. I did what every poor Ram owner does and went to Autozone to have them check things out with their OBDII reader. (Pay attention 'cuz here's where the fun starts.) The guy hooks up the reader and...the headlights come on, most of the idiot lights come on and the odometer says "no bus". Then he gets a "link error" on his little machine. I asked him if there could be a problem with the reader as this hasn't happened before (left the gas cap off when the truck was running about a month ago setting off the "Check Wallet" light). He said that he had recently used the meter successfully.

Is the reader bad? Is there more than one place under the dash to plug said reader into? Could this be some electrical gremlin in my truck? I have an '03 1500 QC 4.7 4wd, completely stock. I have absolutely no problems in the way it runs at the present time. I'd hate to spend $40 at the stealership just for them to clear an old code.

Peace---

Dave

 

I can answer part of your question for sure. There is only one diagnostic port on your truck. Now for the hard part, check the plug in connections on your PCM (not sure where its at on a 3rd Gen) and make sure they are plugged in good. Other people have had this problem before and ended up having to replace the instrument cluster assembly, so you should waste a few minutes and make sure it is plugged in good as well. The way I understand it "No Bus" means that there is no communication and that is probably why you had the link error message. Hope this helps.

 

you also may want to see if the fuse is blown for the link for the obd2 reader, my friend had a ford f-150 my dad hooked up his reader and no connection, went looking at the fuses and bing the fuse for the port was blown, give it a shot

 

Did you get the truck to start? And drive it home?

If all you had was a code before he plugged in the unit, that becomes the suspect.

Maybe it just blew a fuse.

 

Also a little known trick that works on most DCX vehicles, cycle the key off to on 3 times ending in the on position and the odometer will display error DTCs that are stored in the PCM, providing your commuications on the truck is currently operational. The only way you can try to erase them is to unhook the battery for about 15 minutes. Sometimes it works, other times it doesn't.

 

Where's the fuse block?

 

brandoncrone---Your idea worked. I got 2 codes followed by "done". The codes I got were: P0456 and P0440. Anyone have any idea what these mean? Since I got the codes, does this mean that Autozones reader was bad and my trucks connection was good?

 

P0440 Evaporative emission control system malfunction
P0456 Evaporative emission control system very small leak detected.

Did you remove your gas cap and put it on good? If not, try it.