Code po449

[boltazar]

Hi all, this is my first post, yes a newbe, but not born yesterday. My 2000 Serria pops the code po449 every time I clear it with my scan gauge. An old friend, in the repair business for 30 years does all the work on this truck and after replacing the selenoid and checking the wiring to it, he thinks it's the computer and wants to replace it. It seems over kill to me but I'm not an expert, he is. We tried disconnecting the battery to clear the computer, to no avail, the code keeps poping. I would think that the clock and all the preset radio stations would be lost durring this process but I only loose the clock. Is it possiable that there is a small battery in the radio that keeps the pre set stations set, also keeping the computer up and running but the clock stops (looses that hour or so).

Any input would be appreciated, I got to get this thing through inspection.

Boltazar

 

[Molson02536]

Hi all, this is my first post, yes a newbe, but not born yesterday. My 2000 Serria pops the code po449 every time I clear it with my scan gauge. An old friend, in the repair business for 30 years does all the work on this truck and after replacing the selenoid and checking the wiring to it, he thinks it's the computer and wants to replace it. It seems over kill to me but I'm not an expert, he is. We tried disconnecting the battery to clear the computer, to no avail, the code keeps poping. I would think that the clock and all the preset radio stations would be lost durring this process but I only loose the clock. Is it possiable that there is a small battery in the radio that keeps the pre set stations set, also keeping the computer up and running but the clock stops (looses that hour or so).

Any input would be appreciated, I got to get this thing through inspection.

Boltazar

P0449 is an electrical problem with the evap vent solenoid. These tests are only run under very specific conditions, so you may get a light back on in 10 minutes after clearing the codes or 10 days.

The P0449 may be due to a bad vent solenoid, but it's possible it's a wiring issue. Most likely culprit is the solenoid and if the solenoid is stuck open, you're gonna get the P0440. Pay no attention to the time period needed for the codes to set.

With the key ON, there should be power to the pink wire. The PCM then grounds the white wire as necessary to turn on the solenoid. You could try using an external ground on the white wire when the key's on to see if the solenoid clicks.

Keep us posted and is there any other dtc cods like P0440 ???? those two are common together.

Molson02536

 

[boltazar]

Thanks for the reply, Al my friend and mechanic for 30 years said he checked the wiring and all is good. He recomended installing a new computer at this point. I don't know and have to rely on his experience unless someone here has had this problem.

I had a ford 150 4X4 before this and I have to say the GMC is so much nicer.

Thanks for the reply B