Front Defrost doesn't work well, Bad Visibility, 2012 Rav4 limited

[alk]

Dr. Dyno, thank you. I am calling my local Toyota Dealer tomorrow. I'll post an update after I take it in.

[ColoradoRav]

Like I said my a/c does not seem to kick on with defrost mode if the temp outside is at or below somewhere in the low 40s F. But in winter the air is so dry here it does not matter. Summer is when we need a/c plus defrost.

[JuneBug]

Originally Posted by alk

I am still not happy with our 2012 RAV4 Limited. Daily, I have trouble with visibility because of the poor defroster/defogger. It doesn't matter if there is 1 person, or 4 people in the car. It doesn't defog. Temperatures vary outside.

You might want to run this diagnostic procedure and see if any error codes show up:


CHECK MODE PROCEDURE
1. PANEL DIAGNOSIS (INDICATOR CHECK)
(a) Turn the ignition switch to LOCK.
(b) Turn the ignition switch ON while simultaneously
pressing the A/C control AUTO switch and the REC/
FRS switch.
(c) Check that all indicators and the display area are
turned on and off 4 times in succession at 1 second
intervals.

HINT:
After the indicator check is completed, the system
automatically enters sensor check mode.
(d) Press the OFF switch to terminate the panel
diagnosis.
2. PANEL DIAGNOSIS (SENSOR CHECK)
(a) Perform the indicator check.
HINT:
After the indicator check is completed, the system
automatically enters sensor check mode.
(b) Press the REC/FRS switch to enter actuator check
mode.
(c) After the actuator check is completed, press the
AUTO switch to enter sensor check mode.
NOTICE:
The sensor check must be performed again after
the actuator check is completed because sensor
check mode, which starts automatically after the
indicator check, cannot fully detect
malfunctions.
(d) Check the sensor check results displayed on the set
temperature display.

HINT:
• The illustration shows the display when code 21
is output.
• When 2 or more sensor check codes are
detected, the codes are displayed in ascending
numerical order.
• In cases with 2 or more codes, if they are difficult
to read, press the DEF switch to activate the step
operation and display them one by one.
• The codes are displayed in ascending numerical
order as the DEF switch is pressed.
(e) When any sensor check codes are displayed, refer
to the DTC chart (see page AC-39).
(f) Press the OFF switch to terminate the panel
diagnosis.
HINT:
Pressing the REC/FRS switch returns the system to
actuator check mode.

3. PANEL DIAGNOSIS (CLEAR SENSOR CHECK CODE)
(a) Inspect, and repair or replace the malfunctioning
parts.
(b) Clear the sensor check codes.

(1) While pressing the DEF switch during sensor
check mode, press the Rr DEF switch.
HINT:
Sensor check codes can be cleared by removing
the ECU-B2 fuse from the engine room No. 2
relay block for more than 60 seconds.
(c) Perform the sensor check and confirm that normal
code 00 is displayed.

4. PANEL DIAGNOSIS (ACTUATOR CHECK)
(a) Start the engine and warm it up.
(b) Perform the indicator check.
(c) When the sensor check is started after the indicator
check, press the REC/FRS switch to start the
actuator check.
HINT:
Perform the actuator check with the engine running.
(d) Check the temperature and blower levels by hand at
each step while the actuator check proceeds from
step 0 to 9 at 1 second intervals (continuous
operation).

HINT:
Each step number is displayed on the set
temperature display.
(e) To display step numbers one by one manually,
press the DEF switch to activate the step operation.
The step number changes each time the DEF
switch is pressed.
HINT:
• Each step number blinks at 1 second intervals
during the step operation.
• The illustration shows the display when step
number 5 is displayed.
(f) Press the OFF switch to terminate the panel
diagnosis.
HINT:
Pressing the AUTO switch returns to sensor check
mode. __________________
__________________

[Phrede]

Could this be a problem with too much moisture (leaking) in the interior rather than a climate control problem? I do not have that much of a problem with fogging even with the system turned off. One thing is for sure, this is not normal.

[alotawatts]

Great vehicles but Defrost / engineering sucks.

[Dr. Dyno]

Originally Posted by alotawatts

Great vehicles but Defrost / engineering sucks.

You have four Toyotas and you don't know how to operate the defrost on any of them?
Sorry, but if this post is real that's all I can conclude.

[ravenuer]

Originally Posted by Phrede

Could this be a problem with too much moisture (leaking) in the interior rather than a climate control problem? I do not have that much of a problem with fogging even with the system turned off. One thing is for sure, this is not normal.

I agree. I think he has a moisture problem inside the car.

[RayinAlaska]

Originally Posted by alotawatts

Great vehicles but Defrost / engineering sucks.

No problems whatsoever with the defrost on my wife's Rav 4, as it can be controlled by using the defrost function. However, the air is dry in the interior of Alaska, so maybe that makes a difference.

[vanib]

The only thing that I can think about is that you have the air directed towards slush on the mats. In this case, the car just cannot keep up with the humidity inside, even if air is coming from outside.

[Foryota]

One other thing that might be worth considering: I have noticed in my own experience that the cabin air filter can have a trapping effect on moisture, even with the defroster on and the AC kicking in. This happened on our old Windstar and our 2011 Matrix. We bought the windstar in the winter and had a horrible fogging problem, even with both heaters going. I found out we had a cabin filter and checked it (was filthy) and just removed it rather than replace before Christmas. Voila, the fogging was greatly reduced. Our Matrix had the fogging too (could be location - we are in SW Ontario, very humid all year) and so I thought what the heck - removed the filter for the winter and no more fogging. I think what happens is that the cloth filter retains some moisture from inside or the air going through it and it saturates. Worth a try!