92bseries

just put in a climate control, replaced it and the wiring that plugs to the firewall harness. it only comes on when u turn it to speed 4. is there a short somewhere that i need a new harness???

92bseries

ok not sweatin the speed, but now the lights wont work, replaced the harness and a fuse. has my dash harness shorted somewhere??

danomatic93

If it only comes on at speed 4 I suspect the blower motor resistor. The blower motor resistor is bypassed when on full (level 4). To get to it, open the glove box, and flip it all the way down. It's back there.

The light issue is a not a fun one to debug. Do ANY of the lights or buttons light up? or are all of them out?

trustdestruction

^+1

If all your dash lights are out, your dimmer switch is likely toast.

To test it, remove the switch and jumper the harness that plugs into it. Turn the headlights on, and if your dash lights now work, the dimmer switch is bad.

If it turns out bad, I have one for sale for $10 plus shipping.

ihonda

hey i'm having the same problem.. my a/c only turns on with levels 3 and 4... I understand what your saying to do to fix the problem, but what causes this to happen?

RoadXY

There are resistors to slow down the blower speed. If the resistor is broken, the blower doesn't blow at all...

k3tsurui

This is not necessarily true because back in the days when Honda was making switches...stuff was just built very simple...each setting correspond to a certain path and a single inline resistor (commonly known as A/D ladder). It is very unlikely that you blow more than one path at any given time unless you blow something else along that path that is common. I wouldn't be able to tell you what, but I am almost 80% sure that it is not your "switch resistors." Although props to the ppl that thought of this because they are on track. Normally, when you have an electrical issue...it could be a variety of things...open ckt , short ckt, weak ground, no ground...these are a nightmare to t/s...your best bet is to take the harness out and do a simple point to point diode test to make sure you dont have wires shorted to each other...if you do...tape it off...if you dont, tape off the entire harness to make sure that it doesn't touch anything under the dash....and if all else fails....change out the harness....this is the brute approach but it is the least troublesome....just my .02

danomatic93

^maybe on OLD older cars. 92-95 Civics aren't classics... ...yet.

Anyway, almost every car that has the standard 4 blower speeds has a 'blower motor resistor.' It's a module that regulates the voltage to the blower motor via 4 resistors (one of which is 0 ohms, thus no resistance, and allows all voltage to pass - full speed). If you have a car with an 'infinitely' adjustable blower motor speed the speed control can be considered to be a potentiometer (dimmer switch) which regulates the voltage supplied to the blower motor.