b e b

My sisters 06 Accords heater just stopped working. AC works, air blows out - but when its set to the heater, the air wont get warm at all. Just started doing this yesterday, just started and drove car like normal... Cant see why this would happen all of a sudden.

What kinds of things can I look for?

97civicdx

Stuck thermostat

b e b

Thanks! Ill check when I get home later.

b e b

Hoses are fine, engine temperature is fine and warms up fine... Not a stuck thermostat.

BRRR. Its raining and cold ... Sigh.

PowerUser

Could be a few things...
Have you checked the coolent level yet. Make sure it's full in both the radiator and overflow reservoir (be sure to only use honda antifreeze if it's needed!). "cold" level which is 1/3 the way up on the plastic container if the engine is cold or to the "hot" level which is about 2/3 full.

It could also be the temperature motor that moves a valve on the heater core to allow warm coolent to flow through it. That's a bit harder to check.
see pic below and look for #7 (over to the left) in the pic:

That little guy may need the cable (#12 in the pic) to be put back on where it came off of. or perhaps the motor itself (#7) may have gone bad.

redbull-1

It kind of like what PowerUser posted.

But, let's look for the easy thing first. Check that the heater control cable did not come off the heater control valve. If it is off, reattach it. Then for a long term fix, go to an auto parts supply store and buy a very small length of vacuum hose, cut 10mm length of it and attach to the end of the heater control valve arm after the cable was reattached.

If that is not it, then post whether it is a 2-door or 4-door, engine, and trim level (e.g., LX, EX, EX-L, etc.) as some Accords have climate control, etc. and slight differences in components, etc.

b e b

Thanks you guys! I guess now I have something to do this weekend... =T lol

redbull-1

If the cable is attached. Look where the position of the heater control valve arm is at, start the car and change from heat to cold (or opposite of what it was at initially). Now check to see if the valve arm moved. If it didn't, then it can possibly be the air mix control motor or the cable itself.

b e b

Thank you ! I really appreciate all your guys help!

HondaFan6975

Just first make sure to check the coolant level before it's driven again! If it's the cable or any other part as redbull or power user has pointed out you're fine and don't risk immediate damage to the engine, but if it's the coolant level you could destroy your engine if you overheat. You say it's cold and rainy so you may not notice an overheating if it's cold out and you drive short distances. The engine will warm up fast, but if the heater's blowing cold because there's not enough coolant running through the system and you drive it longer or get stuck in traffic you might blow a head gasket and warp the head(s) or block.

So make sure to check the coolant level before it's driven again (and while the vehicle is cool so you don't burn yourself!) even if you don't have time to work on anything else this is a MUST!

david45249

I have a very similar question if someone will help me out. I have a 2002 Honda Civic. I have the same problem but the air from my heater gets hot when the engine has a high RPM. My coolant isn't low. Any suggestions?

David

PowerUser

Bleed the coolant system.

You may also try the civic sub forum for your year civic:
https://honda-tech.com/forums/honda-civic-2001-2005-78/

david45249

Thanks I'll try that. And I wasn't paying attention to where I posted this. I'll use the correct section next time. Thanks for the help.

Pagey

I have the same problem. Replaced the fuse and it worked for a while. Had to replace the battery and it started working now it isn't again. No hot air... heat or defrost. Help!

Amohler1

I am having a similar issue. I just replaced the heater motor and cable that moves it also did the valve. I do get heat if i move it manually. The motor just keeps going in circle and i only get heat or ac it never changes when i change it on the dash. I assume its a computer issue or electrical but not sure. any ideas ?