Audi A6 heating not working, got very hot a couple of times on climate control then went very cold, now only outside temp coming thru system

All 3 are possible problems. A fuse is most likely the problem unless something got spilled leaked its way into the unit. Check all the fuses with a test light first before you try and replace the unit

You likely have a faulty blend door. It could be electrically, mechanically related, or even a broken door. It may be the blend door motor, or possibly the temp sensor.

I have a 2000 pontiac grand prix with a digital climate control system. The heat quit working, it doesn't blow out any heat. Now that it is warm outside the air stopped blowing out any air. The digital temperature on the climate control is not correct. When it states that it is below 30 degrees on the ext and it is warm outside the air wont be cold. Once it starts going above 30 degrees the air gets colder. Today the blower stop working all together. Was told it maybe the climate control unit was bad. You can hear the door opening/shutting when you switch the temp from cold to hot. But there was no heat blowing out whatsoever in the winter time. Could you please give me your opinion on whether or not it is the climate control unit or something else?

This is due to your riostat being either unplugged or faulty. If faulty simply replace. The riostat is located at the other end of the temperature sellection arm/rod/button. You may have to remove part of the heater selector plastic face to get to it. Its an easy do-it-yourself job.

There are four sensors for ambient tempurature and they work in unison to provide information to the temp reading on the dash, the heater control head ( where to direct air, blending of warm/cold/outside/inside air flapper controls) depending on the ambient temp and the inside air temp sensor located just above the radio as well as the sun sensor on the top of the dash as well as the a/c compressor head.

When you start your car, the body control module takes the readings from all sensors, outside air temp located in front of the radiator, air temp sensor located in the airbox ( senses temp of air being drawn in from the outside into the air box), coolant temp, inside air temp sensor and the sun sensor on top of the dash (this is why it takes a few seconds for the climate control system to begine when you start the car). The intake air sensor is 1st priority, inside air second, coolant third, ambient 4th and sun 5th. For instance, if the sun sensor reads the sun is hot but the interior sensor reads cold, the inside akes priority. The goal is for the system to achieve a tempurature inside the car that matches the selected temp. It uses all of the sensors to set the system up to achieve that goal as quickly as possible.

Example; Its mid afternoon, sunny and 40 degrees outside adn your in stop and go traffic. The intake sensor reads 40 degrees, the outside sensor reads 60 degrees (heat from radiator...engine heat protrudes into cabin) and the sun sensor reads high (sun is strong). The system is set for 72. priority one sensor reads 40, inside sensor reads 65, ambient reads 60= system will blow hot air to the floor out put, dash outlets will lightly flow 65 degree air so the sun doesnt roast you yet your feet are cold(if it blew hot air from all outlets, your upper body would be hot but your legs/feet would be cold). as the interior sensor reaches desired temp, air will be distrubuted through thee dash, defrost and floor with the warmest air coming out the floor and defrost, coolest air out the dash vents. Its a complex system!

The two sensors that will screw the system up the most are the intake and interior sensors. the system will function reasonably well with just those two sensors though it wont blend air temps between outlets if the sun sensor isnt working. If the outside sensor fails, it simply uses the intake sensor, if the intake sensor fails it will rely on the front sensor. However, since the intake takes priority over the outside sensor, if the intake sensor sends incorrect resistance info rather than failing, it will take priority and cause the unit to malfunction such as in your case.

The intake air sensor can be changed from the outside with patience. If it where me, I would pay the two hrs labor and let the dealer do it right.

Kevin,
Kevins Small Engine service,
South Berwick ME. 03908

ok looks like it is temp dependent -- in most cases you will probably need a new display or have to get yours reconditioned . what normally happens is that the lcd ribbon cable gets a bit loose -between the lcd and the pcb and this causes intermittent faults . also next time it plays up try heating it up with probably a hair dryer-just be a bit careful.this will probably confirm if it is due to temp---or it could be just dry joints ---try tapping it and see if it comes good

When you change the heat system to read deg C, the outside air temp will also read deg C. To change between F & C press and hold the recirc button on the heat control and then press the + on the drivers side.

yes, very possible. but first check your fluid level, thermostat.

The hot water from your engine cooling system is not getting into the heater core. Check out the valve that admits water into it.

replace the climate control module