Heater Motor..No pwer at the fuse panel

[jimw2112]

My heater blower motor just stopped working on mu 91 civic 1.5, I check the blower moter resistor, all the wiring are in tact. I check for voltage at the control switch, no power to any of the contants in the harness. I did a voltage check at the heater motor fuse in the fuse panel, no power coming where the fuse goes in. Any ideas where I can check for a short?

Thanks,

Jimw2112

[PaulD]

most cars have additional fuses under the hood. Also, you have to have the key on to get voltages ..... just making sure you didn't overlook that

[jimw2112]

If have the key in the second position, so everything lights up. In this position the heater fan normal works even without the motor running. I'm suspecting that the short is between the igntion switch and the fuse panel because I have no power at the switch harness and the fuse panel. Does anybody know where to get a wiring diagram for a Civic 1991 online? My Haynes electrical diagram is worthless.

Thanks

[PaulD]

if you have NO voltage or current draw ... what you have is an open, a short (circuit) usually will become an open after a very short amount of time. The fuse for the heater/AC fan will be marked on the little panel you take off to gain access to the fuse box. If other accessories turn on, then the fuse box itself is getting power. Check the fuse with an actual ohm meter, sometimes it's hard to tell just by looking.

[jimw2112]

Thanks for the reply. I checked the fuse with an omhmeter, the fuse, i even tried a different fuse, still no power coming from the fuse box at the heater/AC blower circuit (where the fuse goes). Do you know which wire goes to the ignition? I have the ignition switch exposed.

Jim

[PaulD]

I think the power for the fuse box inside comes from a "master" fuse box under the hood. Turning the key just activates the power - probably thru a relay (or maybe several relays). I don't think the power for that fuse box actually comes from the ignition switch

[jimw2112]

I've study the fuses in the fuse box under the hood, the only one that comes close to anything to do with the blower motor is a fuse labeled condenser fan motor, I checked that fuse and its it also good. I plan to go to my public library to study the detailed wiring diagram for the 91 civic tomorrow, unless you know of one on the web. Your right about the relays, I just don't know which ones to check next.

Thanks,

Jim