Blower motor

[ST1G]

So, I'm trying to trouble shoot why the blower motor isn't working on my 1987 eta.

I'm getting power to both sides of fuse 20 with a test light. The fuse blew a few times when I was driving the car last winter. I don't get any fan on any setting inside the car. I changed the blower motor resistor with no change, still don't get anything motor movement. The fan motor turns by hand with no noise, or drag that feels 'off'. I don't want to replace the motor if that's not what's wrong, but I'm not sure what else there could be. Is there anything else it could be? I was thinking the switch in the car but I would be surprised if that failed. Any help would be appreciated. It's been 10 degrees or lower here for a week with wicked traffic. It's not fun not having heat.

[ThatOneEuroE30]

Maybe when the fuse blew it fried the motor. Have you tested the switch though to see if the power goes to it.

[Swanny]

[ST1G]

Maybe when the fuse blew it fried the motor. Have you tested the switch though to see if the power goes to it.

I actually just said fuck it and pulled the whole motor out, zip tied it to the plastic piece that covers it, and hooked it up to a wind turbine. It spun like a turbo prop, I'm surprised you didn't see all the corn fields blow over there in Nebraska it was so strong.

So, now I'm thinking it's the switch in the car. I think the electrical system goes like this for the fan.

Switch in car > Relay (good since fuse works) > Fuse 20 (hot) > load reduction attached to blower motor housing for speeds (replaced with new hella unit) > Blower motor (tested with wind turbine).

I don't think the resister gets power unless the switch in the car is turned. I'm not getting any power to it.

I don't drive around with a sloth so I can use the car pool. I think a standard heating system would do me if I can get it working.

[ThatOneEuroE30]

Yea i believe the resistor only gets power when the switch is on cause the resistor controls fan speed. I may be wrong though. I hate
Electrical gremlins.

[JIM1inWisconsin]

A new resister costs about $30 and takes about 30 minutes to install. Do this first. If your blower still does not work the blower needs to be replaced. Replacing the blower can be a little tricky.

[vpilarrt]

When the fan speed switch is on 4 (highest setting) the resister pack is not even in the circuit. So if you get no fan at 4 then its something other than the resistor. Are you getting power to the switch (green/brown wire)? Power out on position 4 is on the blue wire. See pages 6413-0, 6413A-0, 6431A-1 for schematic and troubleshooting: http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf

[ST1G]

A new resister costs about $30 and takes about 30 minutes to install. Do this first. If your blower still does not work the blower needs to be replaced. Replacing the blower can be a little tricky.

You obviously didn't read the thread. I changed the resister already, and have pulled the fan out and applied 12v to it, and it spins great.

When the fan speed switch is on 4 (highest setting) the resister pack is not even in the circuit. So if you get no fan at 4 then its something other than the resistor. Are you getting power to the switch (green/brown wire)? Power out on position 4 is on the blue wire. See pages 6413-0, 6413A-0, 6431A-1 for schematic and troubleshooting: http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf

Now this is actually helpful. Thanks! I think it's the switch, I haven't pulled apart the HVAC panel yet to test the switch. I'm not getting any power at any position. I will go through with the multi meter/test light and see what I'm getting.

[JIM1inWisconsin]

Sorry missed it. Just went through a blower problem myself. Worked only on 4. Swaped out blowers which did not solve the problem until the new resister was installed which then worked for me. Your problem does seem more involved. Good luck.

[ST1G]

Sorry missed it. Just went through a blower problem myself. Worked only on 4. Swapped out blowers which did not solve the problem until the new resister was installed which then worked for me. Your problem does seem more involved. Good luck.

Thanks mate, unfortunately it is more involved. I'm really hoping its the switch, because I don't want to go through the wiring in-between.

[vpilarrt]

BTW, I have a working fan switch if you decide you need one.

[ST1G]

BTW, I have a working fan switch if you decide you need one.

Awesome, I will keep that in mind :up:

[ST1G]

FIXED IT! NOW MY BITCHES CAN BE WARM!

For other members sake, I'll post what I did.

Since I had power at the fuse 20, and no power at the motor connector, but I knew the motor worked I figured it was the speed selector switch. So, I whipped out the Bentley to see what wire got power. Pulled off the HVAC panel and found I was getting no power to Green/Brown, which I should have. So, then I figured it was the junction S230 since, that was the only junction I saw. LUCKLEY, I double checked the Bentley against an online diagram. I then saw C204. Well, turns out C204 is a 9pin connector (it's white in my 1987 with a build date of 9/86) under the dash. It was unplugged -.- I plugged that bitch in, and now get power at the speed selector, and at the positive connector at the blower motor. I don't have the blower motor installed, but I know it spins to 12v, so I'll make sure that the connector at the motor is getting 12v before I install it.

I've learned on both this issue, and the no start troubleshooting on my other car that I need to stop being such a little bitch and just read wiring diagrams.

[ThatOneEuroE30]

FIXED IT! NOW MY BITCHES CAN BE WARM!

For other members sake, I'll post what I did.

Since I had power at the fuse 20, and no power at the motor connector, but I knew the motor worked I figured it was the speed selector switch. So, I whipped out the Bentley to see what wire got power. Pulled off the HVAC panel and found I was getting no power to Green/Brown, which I should have. So, then I figured it was the junction S230 since, that was the only junction I saw. LUCKLEY, I double checked the Bentley against an online diagram. I then saw C204. Well, turns out C204 is a 9pin connector (it's white in my 1987 with a build date of 9/86) under the dash. It was unplugged -.- I plugged that bitch in, and now get power at the speed selector, and at the positive connector at the blower motor. I don't have the blower motor installed, but I know it spins to 12v, so I'll make sure that the connector at the motor is getting 12v before I install it.

I've learned on both this issue, and the no start troubleshooting on my other car that I need to stop being such a little bitch and just read wiring diagrams.

Good now go fix your other car