2003 Deville DTS A/C inconsistent

[John Dunn]

I have recently acquired my first Cadillac - a 2003 Deville DTS with 62k on the odometer. Love the car! The A/C has the annoying habit of blowing warm or hot air out of the passenger side ducts in all positions (panel, floor) Meanwhile, the driver side and rear vents are frosty cold. We picked up the car 4 hours away and on the drive home, I took a shop rag, tore it into smaller bits and blocked the panel vents for a couple of hours to keep from cooking the passenger, halfway home, cold air started blowing from the vents the rest of the way home. Next time I started the car, back to hot air.

I pulled the diagnostic codes, cleared them and pulled again, starting and running the a/c in between pulls. Last round produced the following codes:

IOC B1004

IPM B1327

IPM B0419

I tried to decrypt these using the list found at http://www.caddyinfo.com/dtc_2003.htm but don't feel any more knowledgeable than when I started.

After the last round of codes I did notice that the air coming from the vents while not as cold as the drivers side and rear passenger vents was at least cool (this was with the passenger side temp set to max cold)

Initially thought this might be an actuator door issue, but could it be something else?

[Texas Jim]

B1004 - Keep Alive Memory

B1327 - Battery Voltage Below 9 Volts

B0419 - Temperature control #2 (passenger) circuit range/performance

The B0419 is your problem with the AC blowing hot from the passengers side.

The other two codes indicate that the battery was very low or possibly disconnected.

[IceCold]

Yeah buddy that's your problem, passenger actuator. You have to pull the glove box out to get to it. Not a difficult job, just time consuming. Post back if you have any problems or any further questions.

[John Dunn]

Thanks for the reply, further developments:

The battery codes make sense as I did disconnect the battery, hoping that it would cause the electronics to reset...

Now, the only codes I am getting are 0419 and a IPC U1000 (class 2 comms error) I know what the 0419 is (thanks) and I have been told the u1000 isn't anything to be concerned about. Could they be related?

I was able to get cold air from the passenger side using the following procedure:

~courtesy of Basscat of cadillacowners.com~

exercise the passenger side mix door -

with the engine running -

put the MODE to center vents -

blower on a very low speed -
so you can listen to the door movements -

set the temperature to 60 -

this will close the recirculate door -

and select "full cold" for the mix door -

when everything stops moving -
turn the temp all the way up to 90 -

listen to the doors move -
should be a smooth even-sounding movement - or transition -
not jumpy - or binding -

once all the door movements stop - and is blasting heat -
switch back to 60 -

do this SEVERAL TIMES-
it COULD fix the problem -

It did get the AC to work universally, however, each time I restart the car, I have to repeat the procedure. I assume that means there is a part with an issue that will need to be replaced, does this help to narrow it down? I have purchased this part

http://store.the-electric-connection.com/89018789-temperature-valve-actuator--cadillac-deville-dhsdts--2000-2005-p690.aspx?Thread=True

Can you confirm this is the part you refer to above?