Blower fan replacment for 1987 300SDL

[derick33]

I am trying to reach the blower fan motor to replace it. I searched the threads and did not find anything.

Thanks derick33

[sixto]

You should have searched under the glove box

Remove the passenger side kick panel, remove the lower dash cover (3 screws in the carpet fabric along the edge under the glove box door), remove the blower unit (3 screws up into the airbox), disconnect the wires.

Sixto
87 300D

[derick33]

Sixto,
Thanks for the reply. Where is the side kick panel?. I see the 3 screws in the carpet fabric along the edge under the glove box door.

Thanks Derick

[sixto]

The kick panel is the hard plastic panel ahead of the door. There might be a screw besides the friction clips holding it in place.

Sixto
87 300D

[derick33]

-I removed the side kick panel. I removed the cover of the blower unit and disconnect the wires.

- How does the blower motor come out?

Thanks Derick

[sixto]

Oops, 3 more screws straight up holding the blower.

Sixto
87 300D

[derick33]

- Thanks, removed it.

- Is it easy to remove fan from motor?.

Thanks Derick

[sixto]

Not fun. Measure position of cage on old fan, set cage on a frame, hammer blower shaft off cage. Support new motor and shaft when you press on cage so you don't damage the bearings.

Sixto
87 300D

[derick33]

- Thanks.

derick

[derick33]

Hi Sixto,

- Not getting 12V at the 3 prong plug

- I get around 5.5V at one of the leads and this changes when I change the temperature contol setting.

= I checked the fuse for blower motor and is okay. Also changed it and still no 12V,

= Is there any other device between fuse and blower?

Thanks deruck

[sixto]

The 3-pin connector to the controller/porcupine has a red wire with +12V (not sure in which key positions), a black (not brown) wire to ground, and a yellow(?) wire with the control signal from the PBU with a range to about +7V. Then the red and blue wire to the blower motor - one is a constant high signal of +12V, the other is a low signal of 0V or close to it for MAX and close to +11V for MIN. No chassis ground for the blower motor.

You might try a 15-amp fused wire directly from the battery to pin 2 of the 3-pin connector to see if that gets the blower working. If so, you have a break between the fuse panel and the controller/porcupine. Otherwise it's a bad controller/porcupine ($$$).

Sixto
87 300D

[derick33]

- Thanks for the reply.

- Does this car have a strip fuse in addition to the regular fuse?

Thanks Derick

[sixto]

Good question. I don't know if it was OE by then. Look on the inside wall of the false firewall within a handspan of the master cylinder for a black plastic case with 2 wires.

Sixto
87 300D

[derick33]

- Yes found it and was cracked.

- Mercedes Part No 000 545 2034. Price $2.70

Thanks Derick