2001 Intrips SE Windows Fogging

I replaced the battery in November in Chicago. It might have been colder
than 50 degrees ... I just do not remember back that far. The car did
definitely behave badly last winter too, and the original battery was 6
years old when replaced, but was still going strong! I never suspected this
could have been the problem. In any event, I'll need to wait for warmer
weather to do it again. Thanks again.

Bob

 

two things you can do rather cheaply;

1) Measure the vent temperature (center dash vent), temp dial on
hottest, blower on second from highest setting. Should be around
150* or higher.

2) With the blower running turn the mode dial to MAX AC, if the
sound of the blower changes (gets louder) the recirc door is
working.

 

I do have the HVAC thermometer for this purpose and will measure the exhaust
when the engine is warm. I do not think it is this ... but the
recirculation door has me wondering. Will report results later. Thanks
again to all for all the ideas.

Bob

 

you might look at the floor mates for the moisture source try drivng with the
windows cracked and see if that helps remove the fog
the ac system works when the defrost is on to dehumidify the air in the car and
there is a good chance your ac is inop from a failed evap.coil does the ac
compressor cycle?? when turned on?

 

Aarcuda,
Glenn,
Philthy,

I did the simple dash vent temperature measurement and wanted to post the
results. The outside ambient air temperature this morning on the drive to
work was 20 degrees F and when I arrived at work and with the engine and
compartment fully warmed, the exhaust air temperature got up to 152 degrees
F using a HVAC probe type thermometer inserted about 5" into the dashboard
vane and the blower on medium speed setting.

I also attempted to actuate the A/C and listened for the air compressor to
cycle on, but it did not come on, but I suspect this is because the outside
temperature is below the low temp cutout limit. (The A/C worked fine over
the Summer and Fall.)

Lastly, I tried to see if there was any noticeable difference in the
exhausted air speed or the sound when I had the blower on the highest
setting and moved the control knob between the standard dash setting and the
"recirculated dash" setting, but on both settings I could not tell any
difference. This has me thinking that this may be the most fruitful theory
to explore further at this time.

Perhaps this is a calibration issue resulting from the battery replacement
at a temperature below 50 degrees F as Glenn has suggested? Glenn, would
this re-calibration procedure (waiting till temperature is above 50 degrees
F, then removing the battery cable, waiting 10 minutes, reconnecting, and
then running the vehicle for 10 minutes at idle) impact the recirculation
door setting or is there some other thing you suggest that I can check?

In closing, I was also asked by Philthy to do one additional test and that
was to crack open the windows while they were fogging. I made a 40 mile
drive last night and tried this, but at 70+ MPH, all this seemed to do was
cool down the car and cause the side windows to freeze up sooner. By the
way, it was clear that even with the heat control at maximum setting, blower
on full at highest speed, and with the full defroster setting, the faster I
drove the worse the problem became. This tells me that the wind speed
increases the cooling on the windshield and side windows, and that the
humidity is probably never getting exhausted from the cabin, so just
saturates and constantly re-condenses on the cold windows. In worst case,
it actually then freezes solid making visibility impossible. I finally
found that barely popping open my moon roof to allow the hot air to vent
made the cabin temp more tolerable and maybe even helped a little with
getting some of the trapped moisture out of the car.

Thanks again to everyone for the great troubleshooting tips, at this point I
am optimistic that this is the cause. Thanks also in advance for any
additional pointers on how to troubleshoot the recirculation door on this
base model 2.7L 2001 Intrepid SE.

Bob

 

I dont think it is a heat thing, something is not pulling out the moisture
or keeping it inside the vehicle

Instead of listening, pop the hood and see if the compressor kicks on. And
just because it comes on does not mean it has a good charge.

You should be able to tell. A noticeable differecne will occur when allowing
recirc on and off. Possibly a door or motor problem. Scann tool may be
needed

It is a calibration test of the doors. Suggest Scan tool connection

My 2 cents worth, you have a leak in the system and this is not allowing the
moisture to be removed from the car or the recirc door is inop. Your next
step would be scan tool/ A/C manifold gauge connected to verify properly
charged a/c system

 

Glenn,

After getting back home from work tonight I popped the hood and re-ran the
same test. The control was in the defrost position and the blower was on
full and I suspect that the outside temperature was in the mid-30's F. The
A/C compressor came on, followed very shortly thereafter by the cooling fan.
After a short interval the compressor cycled off and then on again every few
seconds. Even in the warm engine compartment, the return line to the
compressor got cold to the touch quickly so I believe the system was
operating as expected so did not put the A/C gauges on to measure the H and
L side pressures. (BTW, having never measured at this temperature, I would
not have been sure how to interpret the numbers anyway since they would be
radically different from what I've seen at 80 degrees F or so.)

At this point, I still can't hear any change when I move between dashboard
regular and recirculating positions, so believe that the recirculation door
is not working properly. At this point I will wait for better weather and
see if I can look at this assembly a bit closer ... if not, then it goes to
the dealer for repair. Thanks to everyone for their contributions to this
thread.

Bob

 

See if you can put the a/c control head into a self diagnostic mode.

The engine must be running with vehicle not moving.
The Fan Speed set to any speed except OFF.
The Temperature Knob in full cold.
The mode knob must be placed in defrost position
The A/C button can be ON or OFF.
Press and hold the EBL button until the Mechanical Instrument Cluster
Odometer display indicates an "AC00". The body control module will chime
once and the MTC A/C button LED will begin blinking.
Release the EBL button and wait until the MTC A/C button LED stops blinking.
The fault codes related to the MTC head and the climate control unit will
appear on the odometer display in numerical form after the letters "AC". The
diagnostic trouble codes are stored in the BCM and can range between 23 and
51. The odometer display will return to normal operation if no trouble codes
are found. If a problem is found, then the odometer will display the letters
"A/C" followed by the trouble code number. The odometer display can only
show one diagnostic trouble code at a time. more than one diagnostic trouble
code could be in the memory. To scroll through any additional diagnostic
trouble codes, press the A/C button on the MTC head. The BCM will beep each
time the A/C button is pushed. Continue pushing the A/C button and recording
the trouble code numbers until the odometer returns to normal operation
(note the letters AC will disappear).

 

Glenn,

I did exactly as you described and just as you said, the chime sounded, the
AC button started flashing and the odometer area on the dash display went to
"AC00". The system then went through some motions and I could hear the
exhaust switching through the different vents. Within a minute or two the
"show" was all over, the "AC00" disappeared and the odometer mileage
reappeared. (There were no trouble codes displayed.)

I was not sure if I happened to miss a trouble code, so then re-ran the
diagnostic a second time, this time watching the display, but again, no
codes were displayed and it went directly back to the vehicle mileage.

Afterward, I re-checked to see if the blower speed and airflow changed when
I toggled between dash only and the recirculate function, but again, there
was no noticeable difference to my ears.

Does this procedure I just performed supercede the one you described
previously? Did this diagnostic perform the calibration that I should have
done after removing/replacing the battery in November or do I need to do
that when the weather warms?

I will see tomorrow morning if there is any change on my drive to work.
Thanks again for all you have done to assist me with this. I really do
appreciate the effort.

Bob

PS Please say a prayer for the Northern Illinois University families (my
middle son who will be getting the Intrepid is currently in his 3rd year
there) that have been affected by the horrific tragedy that took place on
campus this afternoon.

 

What you did was a self test on the system. The only thing I can say now is
to have the system scanned to see what is going on since no fault codes
were found. I dont think a recalibration will do anything, you can try!! I
hope all is ok with your son

Glenn

 

Thanks again. My son was not anywhere near Cole Hall when this occurred,
but knows others who were nearby.

Bob

 

I did mis read it, my bad. And I still firmly believe that if the ac is
working, and is charged, the only thing that can logically cause this
problem is a clogged drain.

Deke

 

Still needs to be checked ...it is on the list, but at 4 below zero not
anytime soon.

Thanks again