93 accord lx heater controls not switching modes

[pontiacR]

the heater/ defrost buttons on my dash are lighting up but the switches no longer redirect the hot air to the defroster, etc.
only the dash vents are blowing no matter what button is lit up.

my first instinct is to check the heater control relay - anyone have any exp. with this?

physically where is the heater relay anyway? what color wires am I looking for?

[jeffcoslacker]

95% of cars on the road this is a problem with a disconnected vacuum line....look under the hood along the firewall (especially in any area where some work was done recently) and under the dash to be sure one didn't get kicked loose and is hanging...

If the control system is electrical on yours, this won't help. I don't know which you car uses. Most use vacuum to move the plenum door and mode selector routing position. Good luck.

[basszzilla]

I have a 92 accord did the same thing, what I didn't realize was the knob was stripped. It felt like it was switching but wasn't, after about six months the knob fell off from my continued hope that it would just start working, boy did I fell stupid. Don't know if this is your problem but it was all I needed.