I have a 2004 Pacifica with 120,000 miles on it. I am getting a P0403 code, I just had the EGR valve replaced and I am still getting this code. I checked the wiring going to the EGR and nothing looks wrong. Does anyone have any ideas or suggestions? Thanks

 

I also checked the wires running from the harness to the two O2 sensors. Could the notorious intake plentum leak be the cause of the P0403

 

U will need a scanner to make the EGR tiurn on and off my the PCM and then measure the voltage at each connector pins and see which is missing.
Also how did u check teh wires just look or measure voltage and grounds?
and short to ground?

 

I did a visual. I removed some factory tape from areas on the harness that looked kind of rough and found no bare or broken wires. i also made sure all connections to other sensors were good.

 

I just noticed, the area under the battery has multiple ground wires attached to the body. One of the ground wires was barely attached, I pulled it off with very little effort. It comes out of the harness that leads up to the EGR area. I hope this is my problem.

 

Does this solve your problem?

 

Ok, just an update. I checked the ground wire under the battery and 1 of them (the single wire) had a brittle connector that got easily removed. I changed it and haven't seen any error codes yet after a full day ride. *fingers crossed*

 

Hope it works out for you. Your Pac is in the Philippines? Am sure that is an interesting story in itself, must be the only one in country..

 

There's a Chrysler dealership here, but I doubt that they will be able to solve the issue. It's good that we have forum like this where people can support each other