Blower motor problems (searched)
 

(88 TII 5sp) I searched but i could't find specific enough answers. (if someone knows a tread that would answer this feel free).

Anyway, my blower motor stopped working a couple weeks back. To make a long story short, its not the motor itself. It runs when battery voltage is applied. Here's the thing i can't figure out. With the blower motor disconnected, i can test 0-5-12 volts on the power connector for the motor, and both of the relays click. If i reconnect the motor while the switch is a max position, the blower motor will work. As soon as i turn it down from max, it turns completley off, and won't turn back on if i put the switch back to max position. And with the blower motor connected, only one of the relays will click (the square one, not the round one).

Now I'm stumped. Is it the logicon that is causing this, or the relays themselves that are just no good? I've seen a couple people suggest checking the blower resistor, but i cant find anything in the FSM relating to a resistor (is it in the logicon itself?). Last but not least if i should have to switch out the logicon, how the hell does one get to the connector on the end of the long harness coming out the back of it?

Thanks for any help, guys

There is a power transistor on the fan box near the relays.
It controls all but the high speed.
I'd start by checking it.

There is a snap down metal plate on top of the dash, forward of the vinyl.
It goes all the way from the left to the right A-pillar.
You lift it up & out to get to the logicon connector on the higest part of the firewall.
Even with the access panel out, it's still a tight squeeze.

There is a heat & AC section in manual.
The link is in my sig below.

ill check out that transistor in a few, after my back recovers from the last 20 minutes i spent in the ridiculously uncomfortable position on testing blower motor stuff.

While you're recovering, download & print that part of the FSM.
Lots of good info...