Author Topic: e30 Blower fan not working!  (Read 6450 times)

selespeed

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e30 Blower fan not working!
« on: April 26, 2015, 11:50:32 PM »
hi;

turning on the fun doesn't work suddenly. for the past two days it worked occasionally and now it just died totally. there's "swoosh" sound when i turn on the switch, but blower fan doesn't run. Fuse and relay are all ok.

What's wrong?

teo

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Re: e30 Blower fan not working!
« Reply #1 on: April 28, 2015, 04:41:15 PM »
I'd take a look at the fan itself, under the cowling. First test I'd do is a voltage check at the fan wires. ETM suggests switching on the ignition to Run, setting fan speed to high, and turning the A/C switch on. If you see 12VDC on the fan terminals, check the fan motor. If you don't see 12VDC, check the resistor pack for damage.
That resistor pack has an integrated overload breaker, I've seen them fail completely.

If the fan works only on high speed, it's also the resistor pack located inside the fan cage. New packs aren't that expensive.

If the fan doesn't work at all, or squealed a lot before it stopped, it could be seized bearings in the fan motor, or a warped fan cage.

I've never seen an HVAC switch fail, but that's a possibility as well.
'08 Karmesinrot 128i 6MT
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selespeed

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Re: e30 Blower fan not working!
« Reply #2 on: April 28, 2015, 08:26:36 PM »
I'd take a look at the fan itself, under the cowling. First test I'd do is a voltage check at the fan wires. ETM suggests switching on the ignition to Run, setting fan speed to high, and turning the A/C switch on. If you see 12VDC on the fan terminals, check the fan motor. If you don't see 12VDC, check the resistor pack for damage.
That resistor pack has an integrated overload breaker, I've seen them fail completely.

If the fan works only on high speed, it's also the resistor pack located inside the fan cage. New packs aren't that expensive.

If the fan doesn't work at all, or squealed a lot before it stopped, it could be seized bearings in the fan motor, or a warped fan cage.

I've never seen an HVAC switch fail, but that's a possibility as well.

thanks dave. you are right its the motor of the fan. the bushes are worn and i have them lubricated or oiled. however, after putting it back it still emits louder motor noise. i wonder how i am able to get a new motor. it's a Bosch.

the resistor is good. the culprit is the motor. and it works on all 4 speeds. just that the highest speed is now loud. sign of failing soon?

« Last Edit: April 28, 2015, 08:42:47 PM by selespeed »

DesktopDave

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Re: e30 Blower fan not working!
« Reply #3 on: April 29, 2015, 07:29:12 PM »
My fan does something similar at times, but it's not the motor or the bearings. The plastic fan cages have warped a bit over the years, and occasionally drag against the inside of the fan housing. They make quite an irritating screech when that happens.
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS