batmanfc

I have a 91 integra ls and the controls for the vent wont work. The fan speeds and hot and cold work but when I try to switch from the vent to defrost it just keeps blowing through the vent. It will switch to the floor setting or the vent and floor setting but none of the defrost settings will switch over. How can I fix this.

batmanfc

Any help?

NVturbo

Internal control module might be screwed. Pickup another A/C control from your local salvage yard.

batmanfc

Alright I'll give that a try. How is it controlled? Is it vacuum or electrical?

fcm

On your 91 LS there is a mode control motor and a set of levers, make sure motor moves when switching modes and the levers move accordingly... http://www.acuraautomotiveparts.org/...ystemcomp=List All&vinnoT=&trim=&trans=&view=normal

You do have buttons, right?... http://www.acuraautomotiveparts.org/...ystemcomp=List All&vinnoT=&trim=&trans=&view=normal

Or do you have levers... http://www.acuraautomotiveparts.org/...ystemcomp=List All&vinnoT=&trim=&trans=&view=normal

Only seen levers on RS model. 94

NVturbo

The controls are both mechanical and electrical. I don't believe Honda uses vacuum to operate the AC/heat system.

batmanfc

It does have buttons not levers. The first three buttons work but the ones that control the defrost don't. I figured the switches were probably bad. I didn't know if there was any way to check and was hoping that maybe for the time being I could just manually switch it to defrost so the car can defrost and I can unfog it was it starts raining.

fcm

You can test it, pull the HVAC control head, [mode control switch assembly] and unplug it, supply a ground directly to the yellow/blue lead, [deforost] if you get defrost the switch, [button] is the problem, if not, the mode control motor is the problem.

Also check mode lever A, #6... http://www.acuraautomotiveparts.org/...ystemcomp=List All&vinnoT=&trim=&trans=&view=normal in fact check all the levers to make sure they are all "connected", you can see them all if you look up from the drivers side to the top left side of the heater box. 94

batmanfc

Awesome thanks for the info. I will definitely check it to make sure.