I've look through some of the post and was looking for some help. I have a 1999 Disco II that has a 145,xxx miles. The Blowers have quit. Both Front and back. I have what i think is control power the relays from the controller but now power to the motors. I bench tested the motor and it works. I can watch the relays operate but ther is nothing going across the main contacts. I found some the things that have pointed me to the Transistor but am not sure. Is there a way to test this. I pulled it out and all the resistors show open on the ohm meter. Also read some posts about a bad fuse block. Would this be the one under the steering colum? Just incase this helps I had a bad connection at the motor before all this happened. I replace the connection and then a few days later everything quit working. Also replace the main controll in the dash. Thanks for the feedback.

 

Rear blower does not use transistor, but does use fuse 6 under dash, and a fuse inside the resistor pack.

Front blower uses fuse 7 and the power transistor.

Fuse 6 & 7 are fed by fuse link 4 (underhood box), which could take them both out along with other things.

 

I have power to 6&7. Not sure where to go after that. I cant find a diagram on here. Anyone have a link?

 

macassemble link in savannah's sig has electrical diagrams

 

Thanks brOkeit. Here's what I got. It seems the main power wire from the fuse block is dead. So after reading some I'm guessing the main fuse block is shot. Any easy ways to get it out without tearing the dash apart? Harness feel pretty tight and Im afraid of tearing up the harness. Any thoughts? Thanks.

 

So I got the block out and did some checks. Put it back and now have about 7.6 volts to the main relay on the motor. Im guessing all the inconsistant reading would prove the block is bad. Any thoughts?

 

You need to put a load on that connection.
Go get an old school head light.
Wire connections onto the tabs on the head light.
Use the headlight to test the current.
If you can light the high beam on the head light - that's enough to run the blower motor.

You got a burned connection plug or wire somewhere.
the 7.6 volts is residual through a burned or carbonized contact.
That connection probably can't support any current or wattage.

Put a small lamp on like a dome light.
If that small lamp does not light, then wiggle the harness or fuse block until it does.
That's how to find the problem.

 

I checked it at the block and it was 7.6. Pressing the meter lead hard or wiggling it in the block connection the voltage is all over the place. Never over 10.5. On next fuse up its 12.5 steady no matter how I move the lead. I would think that is showing something is wrong with the block itself. I hope! I checked the price on blocks and they are expensive. Can the block be disassembled and solder?

 

If you want to test the blower motor hotwire directly to the battery comes on it works if it doesn't it doesn't..... I'm sure you know what that means

 

I did the fuse panel by-pass detailed bu Jwarn11 on another forum. Instead of cutting and splicing wires, I removed the tabs from the connector and direct wired a Maxi fuse in. Works great!