Hello,

As you can see by the title, my heat isn't working. Even when I slide the control all the way to the hot side, cold air comes out. I have a feeling the heater isn't just "broken" because when I switch which vents I want the air to come out of, sometimes the A/C light will come on. So I'm thinking maybe the slider isn't working and my air temp is just stuck on cold or something.

I have gone underneith the dash and there is one cable connected to the slider which works all the way into the hood of the car (I can see the cable move under the hood when someone is inside moving the slider). I also see room for another wire that could be connected to the slider, but can't find the wire anywhere. I'm not sure if there are supposed to be 2 wires connected to the slider (could someone check theirs?). Other than that, I've checked the fuses (one under the hood and one above the pedals) and they seem to be fine. If anyone has any ideas, my ears are open. Thank you!

 

try adding coolant/water to the radiator... mine sometimes won't work when it is not full.

 

ok, follow the two heater hoses that go into the firewall at the heater valve. there is a cable sytle switch thing there, see if you move that and it makes a difference.

or the heater core could be all blocked up or the heater core could be bypassed all together

 

when i put mine all the way over on heat, my engine temp goes down halfway within seconds.....should i be looking at the same stuff that was said above or change my thermo?

 

I would say change the thermo... If the heater core is bad it might have leaked into the car.

 

I have checked the following:

-the wire on the slider is moving in the engine bay and opening the hose

-both hoses seem to be the same temperature (pretty warm) so I'm assuming coolant is flowing

-the temp gauge on my cluster reaches almost half-way (which is normal) so the thermostat should be fine right?

I have no idea what the problem is. The air coming into the car isn't as cold as the outside temp, but it's still cool; definitely not the normal heat.

 

Its your water valve assembly unit. Follow the cable that goes to the assembly to the right of the battery under your hood. There should be a cable that connects to it. Have someone move your thermostat inside the car from cold to warm (blue to red) and see if the cable moves the valve. If it doesnt move the cable is probably disconnected. Odds are thats what happen. Either that or your heater core (#3 on 2nd diagram) is so dirty its not transfering the heat when the blower blows over the coil. I gave you the parts diagram for the entire heater assembly unit. Your welcome.

Part # 79710-SR3-A01 VALVE ASSY., WATER 1996 CIVIC $32.59

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96CXhatch &raquo;</TD></TR><TR><TD CLASS="quote">I have checked the following:

-the wire on the slider is moving in the engine bay and opening the hose

That's good. But also stick your head under the dash and try to listen to the flap opening and closing when you slide the bar over to the heat side. Do you hear it? Sometimes the little flap/valve breaks. Not too common, but I've heard it happening.

-both hoses seem to be the same temperature (pretty warm) so I'm assuming coolant is flowing

When the car gets to normal operating temperature (and AFTER the thermostat has opened), both hoses should be pretty damn hot, not just "warm." Did you verify that the thermostat was opening? Turn on the car and idle it for a little while. After the car gets warmed up to a point, the thermostat will open. At that point, your temp gauge should drop almost half a centimeter. Several seconds after that, turn on your heat. Any change?

-the temp gauge on my cluster reaches almost half-way (which is normal) so the thermostat should be fine right?

Should be, but check to see if you even have a thermostat. Sounds funny, but sometimes people just take it out. In that case, under certain conditions, your heat coming out won't be very hot at all, because the coolant hasn't had time to "warm up."</TD></TR></TABLE>

Did you check your coolant level, as the second poster suggested. Check it/bleed it. Fill up the radiator. Turn on the car, warm it up. Wait until thermostat opens. Fill the radiator again because the level would have dropped at that point.

 

Thanks for the replies guys

i)the cable is opening the valve (well, it's moving so I assume it's opening)

ii)I'm pretty sure I'm hearing the flap open (it's hard to tell b/c there are many noises like sliding and switching of the rods)

iii)I let the car run a little longer and the hoses became pretty hot, but still no change in heat output

iv)I watched my temp gauge. It rises to about 1/2 a centimetre below the halfway mark, but doesn't drop like you said it should. How do I check if I have a thermo? (shouldn't the fact that my gauge even moves mean I have a thermo?)

v)My coolant is at the MAX line

vi)what are the odds of the cause being a dirty heater core?

Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 96CXhatch &raquo;</TD></TR><TR><TD CLASS="quote">
iv)I watched my temp gauge. It rises to about 1/2 a centimetre below the halfway mark, but doesn't drop like you said it should. How do I check if I have a thermo? (shouldn't the fact that my gauge even moves mean I have a thermo?)

Do you know where your thermostat is? Follow the lower radiator hose and see where it connects to the block. There is a little ball shaped thing that is bolted to the block. If you remove that, the thermostat is there inside. On a B-series block, the cover is held on by two 10 or 12mm bolts. Probably the same with a D-series. Your gauge isn't measured by your thermostat. There is a sensor on the block that does that.

v)My coolant is at the MAX line

Where though? On the overflow reservoir? That really doesn't mean too much. You have to fill it in the radiator. Then bleed it like I said. Run the car, until it warms up. Wait until thermostat opens, then fill up the radiator more. Then cap it off.

vi)what are the odds of the cause being a dirty heater core?

Could be. You could try the ghetto way of flushing it out. Disconnect the two hoses going into the firewall. Put a garden hose on one end. Let er rip. If it comes out flowing smoothly on the other end, then your core shouldn't be clogged. If it's trickling out slowly, chances are you have a dirty/clogged core. I believe there are things you can buy to clean it out, rather than having to remove your dash and replacing it. </TD></TR></TABLE>

 

I heard compressed air is sometimes better than water flushing with garden hose

 

Odds are if you checked just about everything than it is your heater core. Car heat is like radiant baseboard heat in houses. The water is heated by a boiler and when you turn the heat on a zone valve opens and lets the hot water flow through the copper tubing and the heat rejects off of the aluminum fins, just like a car. Clean your heater core out and go from there.

 

i feel this guy i have the exeact same problem in my 96 ex and still havent got to the bottom of it yet

 

whats up man.. listen i got that same damn thing happening with my delsol.. have you gotten anywhere with it.. i got all the info everyone left.. which was great (thanx guys) but with this damn weather i havent been able to check anything yet.. has anything helped yet?

BoostdDelSol@aim.com

 

there is a cable that attatches to the back of the lever... might have gotten disconnected... mine did the same thing and that fixed it.

 

How about you guys start taking pics so we can see whats going on. Start with taking a pic of the water valve underneath the hood. Its to the right of the battery and down a little. A black coolant hose connects to it from the block.

 

Thanks for all the help! I will do the tasks tthis weekend and let you know how it goes. I'll take pics to show the processes.

 

Before I begin, I would actually like to look further into why the A/C light is coming on. It could be something so simple that I am missing. Why would this light come on every time I switch buttons on where I want air to come from (e.g. feet, body, window). I would think that something is stuck on "cool." I don't think this was happening before, so I may have done something to make this so.

Does anyone know how many wires are connected to the white plastic piece connected to the slider under the climate control buttons? I know there is definitely one that travels to the climate "box" and then under the hood. But there also looks like there is a connection for another wire. Just wondering if I somehow disconnected this while putting my CD deck in.

Thanks guys, I just want to see if I can solve the problem through this A/C light before I start disconnecting things.

 

i have a 94 cx model and my heat was not working eather and i check ed the heater blower moter fuse's that wasn't it. mine would act like it was comeing on but it woludn't so i followed the slider cable and it just came off the valve that lets water in to the heater core if that is not it i have no clue also the reason that your a/c light is comeing on is you can run your heat while on a/c it just takes all the moisture out of the heat just check the cable.