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Bob W 12-10-2011 09:32 AM

Cabin temp
This morning very little heat. Rec door working, blend doors replaced and working, new heater core. Fan speeds all work and coolant circ is very good. Is there another door or valve somewhere? :confused:

Frango100 12-10-2011 09:43 AM

Re: Cabin temp
There is also a mode door, which will direct the air to , or the windshield, or the dash vents or to the floor vents. When you say there is a little heat, do you mean that there is a lot of air coming out, but with low temperature, or is there just a low airflow? Also do you have the Automatic Zone Control system, or manual?
Was the system working normally until today?

Bob W 12-10-2011 12:28 PM

Re: Cabin temp
Have azc, air flow very good from top to bottom. Just cooler. Daughter said she thought she heard a noise just before it started feeling cooler.

Frango100 12-10-2011 05:57 PM

Re: Cabin temp
Did you check the engine temperature if its not colder then normal? A stuck open thermostat for example would keep the engine coolant temperature lower and thus also has less heat available in the heater core.
If ok, you could do a system self test to see if any component is failing. There are many fault codes, so if you just tell what you get, i can tell you what is failing:

To enter the AZC self-diagnostic mode, perform the
(1) Depress the a/c and recirc buttons at the same
time and hold. Rotate the left temperature control
knob clockwise (CW) one detent.
(2) If you continue to keep the a/c and recirc buttons
depressed, the AZC control module will perform
a Segment Test of the Vacuum Fluorescent (VF) display.
In the Segment Test you should see all of the
display segments illuminate as long as both buttons
are held. If a display segment fails to illuminate, the
vacuum fluorescent display is faulty and the a/c
heater control must be replaced.
(3) After viewing the Segment Test, release the
A/C and Recirc buttons and the display will clear
If a 0 is displayed, then no faults
are set in the system.
Should there be any faults,
currentor historical, all fault codes will be
displayed in ascending numerical sequence (note no
effort is made to display fault codes in chronological
order). Each fault code is displayed for one second
before the next code is displayed. Once all fault codes
have been displayed, the system will then repeat the
fault code numbers. This will continue until the left
side set temperature control is moved at least one
detent position in the CW direction or the ignition is


Bob W 12-11-2011 08:24 AM

Re: Cabin temp
After talking more with her, my daughter said when she is at hwy speeds the temp drops off. 45mph or slower she has more warmth coming in. I will ck the system for codes when she arrives home today.
Thank you so much for your help with this problem. It has me scratching my head.

Frango100 12-11-2011 02:20 PM

Re: Cabin temp
Then i would first look at the engine temperature, because at the highway there is more cooling airflow true the radiator and the thermostat should close a bit to keep the engine temperature constant. If the temperature goes down during highway rides, i would suspect a sticking or broken thermostat.

Bob W 12-13-2011 06:02 AM

Re: Cabin temp
Engine temp 189/198. screwed in test sensor at top of thermostat to check. does have code of 54 ?

Frango100 12-13-2011 07:25 AM

Re: Cabin temp
Temperature doesn´t seem to be far of. Also the radiator temperature is normally lower then the engine temperature, so that should be ok.
Code 54 means "left temperature door travel too large"
Normally this means a broken end stop or broken blend door itself. The left door actuator is easily accessible when you remove the glove box. You could remove the actuator and move the door by hand to see if its broken or not.
Is there still hot air on the passenger side?

Bob W 12-15-2011 04:48 AM

Re: Cabin temp
Left and rt doors do work with temp control for driver and pass sides. Just for checking I pulled the fan motor down and found fhe rec door stuck sideways and broken. align it up to the grill side and secured it. still same issue, driving hwy speed cooler air starts coming thru ?

Frango100 12-15-2011 05:44 AM

Re: Cabin temp
Is colder air coming from both drivers and passengers side?
If you disconnect the battery for a minute or so, you will delete the memory of the airco panel. Will the same fault code 54 come back after some time? It can be that the fault was not reset before.
You did check the engine temp, did you also check it during highway driving?

Bob W 12-17-2011 05:00 AM

Re: Cabin temp
Cooler air thru both sides. Did not disconnect batt. Will do that then check temp at hwy speeds. Wil get back with results. Thanks again.

Bob W 12-18-2011 04:29 AM

Re: Cabin temp
engine temp 196,199 @ hwy speed. 65mph ?

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