I think I found my problem...I will get back with you if it doesn’t fix the problem.....I’m working on a 74-914. I’m not getting any power to the blower motor located inside the engine compartment. Looks like it has a two wires a brown (ground) and a green one (hot). What powers the green one? From what I can tell it is powered through the relay on the relay board. However, since the ground is supposed to be intermittent (actuates when the red cockpit lever is pulled up all the way) I have the problem where?

IIRC ............ the ground on the lever activates the relay on the relay board. It's the one at the back end. I call it #4. The brown wire comes from the body ground.

try tracing the blower motor power

http://www.914world.com/bbs2/index.php?showtopic=77603

this link shows the relay board and its 12--14 pin connectors.

Has it ever worked?

Another thing to check is the relay and relay socket itself. I'm seeing quite a few car with oxidation inside the female sockets for the relay.

pullup the carpet around the lever and remove the lever. make sure the ground wire is still connected to the lever. no wire, no ground. then you can put a meter on the blower motor harness at the plug and see if you have power out of the relay board.with no power out of the relay board or no ground, all the new blowers in the world wont rectify your problem. also basics, check all your fuses.

I had the same issue. I think injunmort is on the right track, as I went into the lever, didn't really find anything amiss, but when I put it back together it started working again.

Rusty grounds....hot grounds.....hot wire means no wire. That's what I found.

Between rusty relay grounds and a really thin trace on the relay board, bound to fail after 40+ years.

I had to rewire the ground completely from the harness through the tunnel to the harness.

Trace each wire back with a DVM set on OHM's.

Good luck.

Found the problem, loose wire on the heater control. Thanks again for all the help.

Awesome! Now you too can be underwhelmed by the power of the stock heater blower!

I ditched mine a little over a year ago. Just run on engine fan, including in winter. It makes things a little tidier in the engine compartment.