Honda Car Forum

I have a 93 Honda Civic and the heater will not blow no more what could be the problem?

Try popping the hood and looking for a loose wire, or maybe the blower itself its dusty, or sumthing?

If the fan is no longer working, it is more than likely a blown fuse. The fuse panel on that model is either under the dash on the left side or under the hood. It should have a diagram on the backside of the fuse panel cover. Trace the fuse and pop it out and hold it up to a light. If the wire inside is in two pieces, it's blown. Replace it. If the wire inside is intact, then you have a fan or relay problem. the relay is under the hood, but I'm not sure exactly where. Good luck.

Check the fuse boxes under hood and in the car for a relay or fuse that is labelled on the chart to deal with heat or the blower motor circuit, plus check the wires and connections on the blower motor under the hood they could be corroded or rusty and if you follow those wires you should fine the blower motor resistor it could be faulty.Another simple check you could do is disconnect the blower motor and remove it see if its dirty or it's pulley shaft is clogged with hair etc, plus you can unbolt the motor and run wires off it to the battery and see if the motor is in fact turning if it is you know it's not the motor and you might want to check out the blower motor switch. If you pick up a simple 12 volt light tester probe that runs about 8 to 20 bucks at a car parts store etc then you could perform a few basic tests before removing any motor.No1 have the ignition key in the Run position then place the wire clamped end of the probe onto the negative battery post , check both sides of the fuse and if only one side is live that fuse isn't any good and needs to be replaced with the exact same fuse type and amperage of fuse.No2 if both sides of the fuse are live then if any relays in the heat or blower circuit pop out the relay and test the points that you see plug that the relay plugs into"socket" one of the sockets connectors should be live and if not then the relay has either a bad 12 volt positive feed or it has a internal problem" or a fried or burnt circuit inside the fuse box itself. Note that the new vehicles may be using temperature sensors to control the blower motor system and be using comps to control the basic system.No3 if you do find 12 volts at one of the relays socket connectors then pop the relay back in, turn on the blower motor switch at the first level and go to the blower motor connections , use the probe and see if the probe lights up at all.If the probe lights up then try each other level adjustment of the switch, the light should get brighter slightly at each level.Also try replacing that relay if you do find that any power is at the motor with switch on or you find that with it's relay out of it's socket the socket doe's in fact have 12 volts.No4 if no power is found at the blower motor with ignition on run and the blower switch tried at each level then trace the wires and find the resistor circuit for the blower motor, if only one side of that resistor is lighting up the probe or only at one switch setting it's got power then the resistor or switch is faulty.No5 if the probe does lite up at both ends of the resistor and no power was found at the blower motor then the wire going to the blower motor is faulty or has a rusted or corroded connection.No6 if the resistor has no power at any connection and the fuse and relay had power then there is a fault between the relay circuit and resistor or the relay has it's own ground wire and the relay's ground wire is faulty, if so change the wire going to the relay and it should be a black wire, cut the wire as it comes out of the fuse box and attache a new wire same gage to the chassis or the negative battery terminal via a wire o-ring connector etc.No7 if the blower motor doe's light the probe then remove the blower motors ground wire and clean the contacts on the blower motor well, even if no power is found at the blower motor it's vital especially on vehicles subject to extreme weather conditions and over 5 yrs old to clean these connections anyways.No8 try to have patience and go slowly step by step and always double check each troubling shooting test by checking that the probe has a good ground clip connection via using the probe to connect to the postive battery terminal to see if it's lighting and conduct this same battery probe test betwen each test performed.No10 always clean any fuses or relays and connections you come in conduct with with sandpaper a wire brush and file etc.Keep in mind that in most vehicle electrical problems or electrical device failers it's all related to ground wire or connection problems more then likely.It's always best I find to have service manuals for any car or vehicle I own it's helps sometimes a lot. Hope that helps and best of luck.By the way what I'd do is to be sure I've everything in my powers to fix the blower motor problem and to have spare handy common parts that are needed on hand is to go to a big do it yourself auto wreckers find the best blower motor , wiring harnness's, resistors , switches , fuses and relays etc for that same vehicle and remove them bec it's a heck a lot cheaper and faster sometimes when you've the parts at hand.I'd grab a two resistors and I'd try the blower motor right away by connecting to my vehicles battery or by getting the wreckers to test it for you on the spot.

check the fuses, if theyre all good, check the relay, if thats good, your heater fan is blown, if that doesnt work you got a loose wire, my 94 4 door used to blow fuses all the time, especially the heater fan

under your dash on right side is a box mine used to do this too try tapping on it with hammer while car and heater switch is on sometimes it will come back on but eventually you will have to replace blower motor cause its shorting out i found one cheap at wreaking yard good luck