There is a wire and small bulb attached to the back of the blower fan switch (the one that controls the blower fan speed- off, low, med, med/high, high). The bulb goes into a clear plastic plate that backlights the climate control cluster. It's probably burned out, you may be able to buy it from toyota parts over stock our at the dealership. Part 84730B on this diagram SWITCH & RELAY. Fits: RAV 4 | ToyotaPartsOverstock.com

It's normal that the air doesn't get hot until the engine warms up.

 

There is a wire and small bulb attached to the back of the blower fan switch (the one that controls the blower fan speed- off, low, med, med/high, high). The bulb goes into a clear plastic plate that backlights the climate control cluster. It's probably burned out, you may be able to buy it from toyota parts over stock our at the dealership. Part 84730B on this diagram SWITCH & RELAY. Fits: RAV 4 | ToyotaPartsOverstock.com

It's normal that the air doesn't get hot until the engine warms up.

Thanks. I don't know how to get behind the panel, though. Do I have to remove the entire dashboard or something?

And the heat definitely doesn't work at all. I took a 500-mile roadtrip and the heater never produced any heat. All I ever got was warm air that would waft in across the engine if I had the vents open to the outside.

Re: bleeding, I'll ask the place. Is this something I could do myself to fix it?

 

About the lack of heat, when the radiator was replaced was the system bled to get rid of any air which could be trapped in the system? When the system is bled the heater heat control needs to be in the full On setting.

 

You don't have to take the dash apart thank god. Two screws hold a trim piece around the stereo. Once you remove the trim piece you can pull the wire and bulb out from between the stereo and climate controll pannel. I'll see if I can take some pictures after work.

Sorry to hear about your road trip, a few questions. Does your engine temp get up to normal temp (middle of temp guage) when it's cold outside? I had a bad thermostat that was stuck open, when driving downhill in cold weather the temp guage would drop and the heater would barely blow warm.

When the engine is hot and the heater is on, feel the two heater hoses that go into the firewall. If one is hot and the other cold that may indicate the heater core is clogged or has air tapped in it.

 

The temperature gauge does indeed get to the middle, like it normally would.

I'd greatly appreciate the photos. Also, could you point out which two hoses you're referring to?

The auto shop theorized that it could be low coolant, but I checked under the radiator cap and the fluid is still visible above the top . . . shiny metal thingy? Cooling vane? Anyway, it's not low coolant.

 

Here are the two heater hoses, they are the black rubber hoses attached to the silver pipes coming out of the firewall.


Remove the two screws from under the stereo and pull out the plastic trim part.

 

Pull the little knobs off the climate control switches.

 

Use a flat tip screwdriver to pry the face plate off from each end of the climate control unit and pull out the AC button straight out. You don't have to disconnect any wires.

 

The bulb plugs into the center of the backside of the clear plastic plate where my screwdriver is pointing. To the left of my screwdriver you can see part of the blue wire, it comes from the back of the blower fan switch, the light bulb is attached to the other end of it.

 

You'll have a little more room if you remove the hazard switch. From underneath and behind push in on the sides of the switch and push out, then unplug the switch.

 

If you look up from underneath you can see where the bulb plugs in if you follow the blue wire.


I found it easiest to use a pair of needle nose pliers from underneath and pull the bulb socket straight back. Once it's loose from the housing pull it down and pull the bulb straight out from the socket.

 

I found the bulbs at O'Reilly's (#2721) for $5.40. Take the green rubber off the old bulb and put on the new one. Plug it in, turn on the lights and make sure it lights up ok.

 

The hardest part is getting the bulb pressed back up into the hole. Once again the pliers come in handy for getting it into position then you can push it in till it locks with your fingers. It took me a few minutes to get this right.


Reconnect the hazard switch put it back in place, pop the face plate back in place, then put the AC switch back in.

 

Push the knobs back on the switches, put the stereo trip part back and replace the two screws. Test the lights again and you should be good to go. Mine burned out a month after I rebuilt the switch so I needed to replace the bulb anyway.


I hope this helps, sorry for the crappy cell pics.

 

Thanks a ton for the advice on the light. I'll see if I can find the bulb, and then I'll give it a try.

I checked the pipes. The left one was cold, the right one was hot. What to do now?

 

hoses to firewall for heater core

just for future use if in case someone needs a visual.

from Rav4 2009 Base 4WD

above hose is the inlet, warm or hot to touch
below hose is the outlet, going back to where? , cooler to touch than the inlet hose.

 

You can try to back flush the heater core. I've never done it myself but what comes to mind is to make sure the heater switch is set to hot, disconnect the hoses from from the pipes coming out of the firewall, attach two lengths of heater hose to the pipes.

Run the hose from the hot pipe down to a bucket or jug to hopefully catch the gunk that comes out, then use a water hose or compressed air through the cold hose to force whats clogging the the heater core out the other hose.

If you search youtube for flushing a heater core you'll probably find a few different methods, or get a better idea of how to go about it. Good luck.

 

Hm. The auto shop supposedly did a coolant flush when they replaced the radiator. Would that not have been sufficient to clear out any blockages? I don't want to unplug things if it would be redundant.

Again, I greatly appreciate all the information. Have a Happy Thanksgiving.

 

I'd ask them but the fact coolant isn't flowing through the heater core suggests they didn't flush that part of the system. They probably just did the radiator/engine block.

Have a great Thanksgiving.

 

Happy Thanksgiving! Sorry you're having all this trouble!

I just replaced my thermostat yesterday; I'd been running without much heat for a few weeks, so I know it's not fun! I'm replacing my sister's today, too, because the thermostat on her '99L went out, as well! She got about 165K miles outta her thermostat, and I got about 155K miles (can't complain, really).

Did your heater work before the visit to the shop? If your heater worked fine before the radiator replacement, I think you might simply have air in the coolant system. When you open up a drained coolant system to the outside air, you allow a LOT of air to get trapped in the hoses. Its normal (you can't really prevent it unless you change your coolant on the Moon or something!), and the step to remove the air is bleeding the system.

It sounds like perhaps the shop didn't do a complete bleed; it wouldn't surprise me if that's that case. Again, I just did this yesterday, so I can tell you first-hand that it takes a WHILE to bleed out the air after opening up the system; it took me a good 20 minutes. Its possible that the shop didn't realize this, or maybe took a short-cut.

If you'd like to try to bleed the system yourself, its really easy! I recommend getting a Lisle No Spill Funnel, because it makes the job super easy and clean. Bleeding the system without a funnel is going to get coolant all over the place (I know, I had to do it that way before!). The funnel is so much better. They're about $25, which is kinda expensive, but I'm SO glad I bought one because I use it all the time. Its really worth the $25, you can get them at any auto parts store because they are super popular (because they're so helpful).

Basically, you wait till the coolant is cool, and you remove the radiator cap. Have some distilled water or pre-mixed coolant of the same kind as what they added, because when you displace the air bubbles, you'll have to add more coolant.

Do these steps:
1.) You place the attachments marked "C" from the Lisle kit in place of the cap, and push the funnel into the attachment.
2.) You get in the car and push the heater controls to HOT (you don't have to turn on the fan), turn on the engine, and hold the pedal down to get up RPM's to about 2000-2500 rpm. Its easier if you have someone helping you to press the pedal, but it you do it alone and just go back from forth from the radiator to the pedal.
3.) At this point, if you look inside your funnel and you see all kinds of bubbles coming out, you'll know that your system was not properly bled. You can bounce the bumper a little and likely see more bubbles coming up. Pour some coolant or distilled water into the funnel to raise the level to about 1/3 or 1/2 full.
4.) Continue the bleeding process by running the engine in this condition for at least 15 minutes. It was cold last night here, so it took a good 20 minutes to bleed my system out. You need to be sure that the cooling fans behind the radiator come on (you'll hear them, or if you're in front of the engine, you'll hear and see them come on; they only run for about 10 seconds and they're loud) because then you'll know for certain that your thermostat opened and therefore that you have full circulation. Continue doing this till you don't see bubbles--bounce on the bumper up-and-down and back-and-forth, to make sure there's no extra bubbles. It takes a while...don't worry, you'll get the air out.
6.) Once you think the air bubbles are out, shut off the engine, and look at the coolant level in the funnel; as the engine cools, you'll see the level in the funnel drop. Keep an eye on this, and don't let the funnel go empty, because you'll just them re-trap bubbles as you add more coolant. If you can watch it, then watch it, and keep adding a little bit of coolant or distilled water to the funnel. If you have to go inside, then just fill the funnel up near the top with coolant and come back in 15 minutes to check it. Once the car is completely cool (last night at ambient temps, this was about 1 hour after shutting it off), plug the funnel with plug attachment and remove it. The coolant level should be right up to the neck/"throat" of the radiator filler spout. Put the cap back on.
7.) Look at the level in the reservoir--make sure its between the COLD and HOT marks; pour coolant from the funnel into the reservoir to make it about 1/3 or 1/2 way between the COLD and HOT levels.

If after all of this action you STILL don't have heat, then it might be the heater core blocked. If that's the case, then the regular thru-direction flushing that they did won't free anything, because you usually have to back-flush the heater core to free a blockage (disconnect the hoses shown earlier and run fluid IN the outlet so it comes OUT the inlet). But again, if your heat was working fine before the visit to the shop, I'd bet its just air in the system after all the work. If you're temp gauge if getting up to normal, then its probably not the thermostat being stuck open.