heater blower

[fogcity]

In short, what is the best path to follow in getting my heater blower (in engine compartment) to blow? I checked the fuses, what's next?

Thanks.

[pmajka]

pull heater levers, check voltage of wires going in to rear heater blower, if you have voltage, replace blower,

If no voltage, inspect the levers themselves. As you pull them up, they engage a contact switch.

could be really dirty.

[fogcity]

Which wires would they be?

[safe]

The one that connects to the blower.

[safe]

Here is a closeup of the area with the blower removed. In the circle are the connector (and mounting bracket for the blower) you need to check for voltage.

[fogcity]

Thank you.

[austria3]

can you tell me where the ohter end of that cable (red arrow) is located?

I have some problems with the cround cable on this one

Thanks

[juanbenae]

it is more tham likely a motor that has gone south if the other checks don't reveal a problem.. they just don't last that long. backdating the heat is a very good solution. good heat, less clutter in the box (hehehe i refered to a "cluttered box") and a much cleaner look.

[Mysterytrain]

Here is a circuit layout for the SC:


Pretty simple stuff..the red levers have micro switches under them that connects pin 85 of the blower relay [again in the rear fuse panel ] to ground via the starter circuit. Why? well so when you crank the starter the blower doesn't operate. Once the relay is activated the contacts close connecting pin 30 to 87 and sends 12 volts to the blower. Hopefully you have a VOM so you can troubleshoot the system. So, you need to have power at the fuses. You need to be able to trigger the relay to make it work. If the relay clicks then you should have 12 volts on the blower connection, the connector in the picture. If you do then the blower is bad or the ground is bad. Ground the other connection on the blower with a jumper to the chassis. If the blower works you got a bad ground. Test the ground connection with the VOM. Also, an easier way to test the blower is to attach a wire from the blower to one of the hot fuses in the rear panel and then ground the other lead of the blower.

[911Atlanta]

Also could be the "Engine Compartment Relay" shown in that diagram above. It's a small silver box that contains a few relays and a printed circuit board, etc. and it controls the entire heater system. That relay, which is sometimes called a "controller", is behind the curved black plastic panel on leftside of engine bay, held in place by two wingnuts. If it's dead, nothing works. Do a search to get good discussions of this item -- there have been some very informative threads here in the last few months. I'd troublshoot the cheapest / easiest items and work backwards. On my '87, the relay controller was fine but the blower was dead. If the main engine compartment blower doesn't work, the two footwell blowers won't work. Good luck !

[fogcity]

Thanks guys. I found that I have current to the blower (the first time I ever checked this - one wire showed current, the other didn't, so I assume that other wire is a ground, yes?). On any account, I took apart the blower motor, visually inspected the parts, broke some things, glued it back together and reassembled the thing. Now, when I pull the red handle I hear cracking sounds coming from the blower motor, which I didn't hear before. So in my round about way I can say with pretty good certainty that the fault is in my blower motor.

There was a thread here suggesting a cheaper alternative to the OEM blower motor - anyone have any luck with such an option? Also, I managed to break the wire to the up/down heat flow lever in the dash (the bottom of the three levers). Is replacing that wire pretty straight forward?