Link for trouble codes ?

[Tractor Mike]

Anybody have the link for the page that lists trouble codes... I can't find it for some reason.



My truck's check engine light came on today, and I notice that it bogs down badly before it shifts out of 1st gear (2005 auto trans).



Got home & checked for a code... shows P0720.



Any ideas ?



Thanks.



Mike

 

[Matt400]

Don't click on the Dodge logo, just scroll down the page here:

OBD-II Check Engine Light Trouble Codes

 

[Tractor Mike]

Thanks, Matt... "Output Speed Sensor Circuit Malfunction" Never heard of that one before. Wonder why it made the truck bog down so bad. Man ! I hate taking this thing into the dealer !

 

[Motorhead]

You can also search "P0720" in a google search on your computer. I have used this alot because it can cover how to fix the problem.

 

[Matt400]

Some more info. .



That fault code will set when the monitored speed (by the wheel speed sensors) is above 15 mph and the transmission output shaft speed is below 60 rpm's for 2. 6 seconds or more when the engine is running and its not in park or neutral.



Basically the ECM doesn't want to see wheels turning faster and out of sink with the trans output shaft.



Since the fault will set when you reach 15 mph this could put the system into a reduced power/limp mode that you experience causing your bog before an up-shift. Many things such as a short to ground, power or another circuit in the output speed sensors circuit can cause this but if the trouble is intermittent you might want to look close at the sensor itself.



The resistance of the sensor should be between 300 and 1200 ohms. It is located on the transmission case, drivers side near the bottom. Just unplug the connector and test resistance across the pins on the sensor. 4799061AB is the part number and is $37. 65 list at the dealer.



Not saying that is whats wrong, just what I would look at first.

 

[Tractor Mike]

Good stuff ! I'll get out the multi meter & check it today. Thanks !

 

[Tractor Mike]

Update : Now that I knew where to start looking, I went to check the sensor, and found it snapped clean off !! Sure did help to know approximately where to start looking . I'll replace it tomorrow if I can get a new one at the dealer. Does the code clear on it's own, or does it have to be reset witht he diagnostic tool ?

 

[donnier]

Here is another link to trouble codes for our trucks.

Obtaining engine diagnostic codes Ram 3rd Gen by 94rt10ohio - DodgeForum.com

 

[Matt400]

Does the code clear on it's own, or does it have to be reset witht he diagnostic tool ?

After several drive cycles where the truck has been shut off, restarted and then run above 15 mph it may reset and turn the lamp off. If not you can disconnect both neg battery cables for 10 sec and that will do it.

 

[bighammer]

Sag2 typed in (or magically pasted) the whole list from the service manual. I made it a sticky thread at the top of the 3rd Gen (non engine) forum a long time ago. I just stickied it to the top of the 3rd gen 5. 9 forum also. Thanks sag2

I've got a new issue with mine and just looked up that list. I had my light come on last night and I got a 633, 646, and 341.

The 633 must be from when I lost a key and tried to get a non-chipped key to work quite a while back. The 646 is because I removed the A/c garbage that was in the way of fixing my defrost door, so I can see why that code is there.

The concern and reason for the engine light is the 341 cam sensor code. After some searching, it sounds like a failing lift pump, CP3 pump, and wiring harness gremlins can all cause this. I'm not sure if I should take it to the dealer, start replacing stuff myself, or transplant my old 12 valve into the new truck.