QuestionQUESTION: The passenger side vents will start fine, blowing hot air. But after a while of driving, the heat will diminish and become cold. If I turn down the temp on the passenger side and after a couple minutes turn it up, hot air will come out but only for a short while. The dealer repair shop says its the blend door (which I already had replace 2 years ago). But I cannot understand why I get hot air at the start before turning cold (like a hot water heater that runs out of hot water). I am thinking that it should be a thermostat problem. Any assistance would be appreciated.
ANSWER: coolant full? both heater hoses hot? does the temp gauge drop down when u drive or have no heat?
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QUESTION: I don't know the answer to your reply. The odd thing is that only the passenger side vents are affected. I still get heat out of the driver's side vents. I have dual zone controls. I find that if I turn down the temp for the passenger side for a few minutes then turn up the temp, heat will come out for a while. It will then gradually turn cooler. I would love to have you look at my car but I live in Canada. The dealer repair shop can only guess that it is a blender door problem. Can this be? I feel it is a temperature guage issue as I don't change any of the directional flow. I am getting 2nd opinions from other shops. So any information that you can give me to ask of the shops would be appreciated.
Thank you for your help. I really appreciate it.
Answerpossible blend air doors broken again if they did not put the updates ones in the last time then yeah they will brake again there is a tsb for the updated parts. And the dealer can pull the codes for the issue if they are broken it will be pass blend range to large. u can do it yourself as well read this.
ENTERING THE AZC SELF-DIAGNOSTIC MODE
To enter the AZC self-diagnostic mode, perform the following:
Depress the A/C and Recirc buttons at the same time and hold. Rotate the left temperature control knob clockwise (CW) one detent.
If you continue to hold 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 heater-A/C control must be replaced.
After viewing the Segment Test, release the A/C and Recirc buttons and the display will clear momentarily. If the display remains blank then no faults are set in the system. Should there be any faults, either "current" or "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 turned "OFF".
FAULT CODE TESTS
Fault codes are two-digit numbers that identify a circuit that is malfunctioning. There are two different kinds of fault codes.
Current Fault Codes - Current means the fault is present right now. There are two types of current faults: input faults, and system faults. If the system has a current fault when the ignition is turned "ON", or during normal operation a current fault occurs, the right side set temperature digits will display "ER" at maximum intensity, while the left side set temperature digits are blanked.
Historical Fault Codes - Historical or stored means that the fault occurred previously, but is not present right now. A majority of historical fault codes are caused by intermittent wire harness or wire harness connector problems.
CURRENT FAULT CODES
Input faults 01 = IR thermister circuit open
02 = IR thermister circuit shorted
03 = Fan pot shorted
04 = Fan pot open
05 = Mode pot shorted
06 = Mode pot open
07 = IR sensor delta too large
08 = Reserved
09 = Reserved
10 = Reserved
11 = Reserved
12 = Reserved
System Faults 13 = AI (Recirc) motor not responding
14 = Mode motor not responding
15 = Left temperature door not responding
16 = Right temperature door not responding
17 = AI (Recirc) door travel too small
18 = AI (Recirc) door travel too large
19 = Mode door travel range too small
20 = Mode door travel range too large
21 = Left temperature door travel too small
22 = Left temperature door travel too large
23 = Right temperature door travel too small
24 = Right temperature door travel too large
25 = Calibration check sum error
26 = Engine coolant temp bus message missing
27 = Vehicle speed bus message missing
28 = Engine RPM bus message missing
29 = OAT bus message missing
30 = Display intensity bus message missing
31 = VIN number bus message missing
32 = Reserved
HISTORICAL FAULT CODES
Input faults 33 = IR thermister circuit was open
34 = IR thermister circuit was shorted
35 = Fan pot was shorted
36 = Fan pot was open
37 = Mode pot was shorted
38 = Mode pot was open
39 = IR sensor delta was too large
40 = Reserved
41 = Reserved
42 = Reserved
43 = Reserved
44 = Reserved
System Faults 45 = AI (Recirc) motor was not responding
46 = Mode motor was not responding
47 = Left temperature door was not responding
48 = Right temperature door was not responding
49 = AI (Recirc) door travel was too small
50 = AI (Recirc) door travel too large
51 = Mode door travel range too small
52 = Mode door travel range too large
53 = Left temperature door travel too small
54 = Left temperature door travel too large
55 = Right temperature door travel too small
56 = Right temperature door travel too large
57 = Calibration check sum error
58 = Engine coolant temp bus message missing
59 = Vehicle speed bus message missing
60 = Engine RPM bus message missing
61 = OAT bus message missing
62 = Display intensity bus message missing
63 = VIN number bus message missing
64 = Reserved
65 = Reserved
66 = Reserved
67 = Reserved
NOTE: A battery disconnect will erase all faults stored in Random Access Memory (RAM) of the AZC control module. It is recommended that all faults be recorded before they are erased.
RETRIEVING FAULT CODES
To begin the fault code tests, depress the A/C and Recirc buttons at the same time and rotate the left temperature control knob clockwise (CW) one detent, then release the push-button.
If there are no fault codes, the "00" display value will remain in the VF window. Should there be any codes, each will be displayed for one second in ascending numerical sequence (note: no effort is made to display faults in the order they occurred) The left side set temperature display will be blanked and the right side set temperature display will indicate current and historical codes (8 historical max) presently active. Once all codes have been displayed, the system will repeat the fault code numbers. This will continue until the left side set temperature control is moved at least one detent position in either direction, by pressing both the A/C and Recirc buttons at the same time, or the ignition is turned off. Record all of the fault codes, then see the Current and Historical Fault Code charts for the descriptions.
CLEARING FAULT CODES
Current faults cannot be electronically cleared. Repair must be made to the system to eliminate the fault causing code. Historical fault codes can be cleared manually, or automatically. To clear a historical fault manually, depress and hold either the A/C or Recirc button for at least three seconds while the display is in the fault code mode of operation. Historical fault codes are cleared automatically when the corresponding current fault code has been cleared, and has remained cleared for a number of ignition cycles. The faults have been cleared when two horizontal bars appear in the Test Selector display.
EXITING SELF-DIAGNOSTIC MODE
The self-diagnostic mode can be exited by pressing both the A/C and Recirc buttons at the same time, or turning off the ignition.
