Aux Fan Relay

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cory58
Posts: 142
Joined: Thu Aug 25, 2016 8:49 pm
Location: Charlotte, NC

Aux Fan Relay

Post by cory58 »

In all my BMW adventures, this is the first time I've ever tried to replaced a relay!

I would like to replace the aux fan relay on my '77 530i. The current relay is a Bosch 0332014406. No luck so far finding that part number new. Does anyone know if the current BMW part number is 61311373588, which superseded 61311373585. Tough to tell from RealOEM.

Thanks, Cory
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2000 M5
2015 328i (wife's daily)
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Robert Bondi
Posts: 325
Joined: Sun Jan 11, 2009 12:33 am
Location: Austin, TX

Re: Aux Fan Relay

Post by Robert Bondi »

Good question. There do seem to be an excessive amount of part numbers on these cube relays and seemingly
multiple supercession lineages. I've got these two relays in use in my fuse boxes on multiple vehicles:

Bosch (black plastic case): 0 332 019 451
Bosch (orange plastic case): 0 332 019 456

These are somewhat generic...key specs are 12V, 30A, no diode, 4 pin, sanity check of match pin numbers
and orientation of the male blade terminals...

I ran into some suspect counterfeit stuff once. They were branded Wehrle and stamped as 'W. Germany' and dated '99'.....
hmmm....OK. I've stuck with Bosch ever since...or at least it's labeled Bosch...never really know any more.

Sometimes, just reseating them helps and I always carry a spare.
Robert
77 530i
77 Euro 528
cory58
Posts: 142
Joined: Thu Aug 25, 2016 8:49 pm
Location: Charlotte, NC

Re: Aux Fan Relay

Post by cory58 »

Robert Bondi wrote: Sat May 14, 2022 2:16 am Good question. There do seem to be an excessive amount of part numbers on these cube relays and seemingly
multiple supercession lineages. I've got these two relays in use in my fuse boxes on multiple vehicles:

Bosch (black plastic case): 0 332 019 451
Bosch (orange plastic case): 0 332 019 456

These are somewhat generic...key specs are 12V, 30A, no diode, 4 pin, sanity check of match pin numbers
and orientation of the male blade terminals...

I ran into some suspect counterfeit stuff once. They were branded Wehrle and stamped as 'W. Germany' and dated '99'.....
hmmm....OK. I've stuck with Bosch ever since...or at least it's labeled Bosch...never really know any more.

Sometimes, just reseating them helps and I always carry a spare.
Thank you! Great info. Several of my usual BMW parts sources have Wehrle relays as replacements for the BMW part # I listed in the OP. A couple of follow-up questions.

1. Do you use either of the Bosch part numbers you listed for the aux fan in your E12 (the relay sitting next to the fuse box, not in the fuse box)?
2. You said to match volts, amps, number of pins and pin numbers/orientation. Is it also important to match the operational diagram printed on the relay? In other words, are there relays that match everything you listed but have different functions?

Thanks, Cory
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2000 M5
2015 328i (wife's daily)
tlake
Posts: 418
Joined: Wed Feb 03, 2010 6:33 pm
Location: WA

Re: Aux Fan Relay

Post by tlake »

cory58 wrote: Sun May 15, 2022 8:58 am
Robert Bondi wrote: Sat May 14, 2022 2:16 am Good question. There do seem to be an excessive amount of part numbers on these cube relays and seemingly
multiple supercession lineages. I've got these two relays in use in my fuse boxes on multiple vehicles:

Bosch (black plastic case): 0 332 019 451
Bosch (orange plastic case): 0 332 019 456

These are somewhat generic...key specs are 12V, 30A, no diode, 4 pin, sanity check of match pin numbers
and orientation of the male blade terminals...

I ran into some suspect counterfeit stuff once. They were branded Wehrle and stamped as 'W. Germany' and dated '99'.....
hmmm....OK. I've stuck with Bosch ever since...or at least it's labeled Bosch...never really know any more.

Sometimes, just reseating them helps and I always carry a spare.
Thank you! Great info. Several of my usual BMW parts sources have Wehrle relays as replacements for the BMW part # I listed in the OP. A couple of follow-up questions.

1. Do you use either of the Bosch part numbers you listed for the aux fan in your E12 (the relay sitting next to the fuse box, not in the fuse box)?
2. You said to match volts, amps, number of pins and pin numbers/orientation. Is it also important to match the operational diagram printed on the relay? In other words, are there relays that match everything you listed but have different functions?

Thanks, Cory
Jaymic in the UK seem quite knowledgeable about replays. They got me a brand new one concerning the turn signal indicator.
User avatar
Robert Bondi
Posts: 325
Joined: Sun Jan 11, 2009 12:33 am
Location: Austin, TX

Re: Aux Fan Relay

Post by Robert Bondi »

cory58 wrote: Sun May 15, 2022 8:58 am

Thank you! Great info. Several of my usual BMW parts sources have Wehrle relays as replacements for the BMW part # I listed in the OP. A couple of follow-up questions.

1. Do you use either of the Bosch part numbers you listed for the aux fan in your E12 (the relay sitting next to the fuse box, not in the fuse box)?
2. You said to match volts, amps, number of pins and pin numbers/orientation. Is it also important to match the operational diagram printed on the relay? In other words, are there relays that match everything you listed but have different functions?

Thanks, Cory
1. Yes, either should be good for the aux fan. I don't think there's really anything special about it....they just ran out
of room inside the fuse box is how I see it.
2. It's hard to say the extent of every part available, but yes I'd match the circuit diagram on the side, which also contains some of the things I listed like pin numbers, no diode, etc....
Robert
77 530i
77 Euro 528
cory58
Posts: 142
Joined: Thu Aug 25, 2016 8:49 pm
Location: Charlotte, NC

Re: Aux Fan Relay

Post by cory58 »

Thanks for all the responses. Once I determined that I could use a relay with resistor, it was easy to find a replacement. Unfortunately it didn't fix the problem (aux fan works fine with AC on but will not turn on from high water temp). More electrical troubleshooting to do - fun!
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2000 M5
2015 328i (wife's daily)
User avatar
Mike W.
Posts: 2653
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: Aux Fan Relay

Post by Mike W. »

cory58 wrote: Fri Jun 10, 2022 2:40 pm Unfortunately it didn't fix the problem (aux fan works fine with AC on but will not turn on from high water temp). More electrical troubleshooting to do - fun!
Assuming the wiring is good, which is really easy to test, you have at least a couple of possibilities, #1 a bad fan switch, and for the price it's worth just throwing a new one in there, and a restricted radiator. A restricted radiator will cause the car to run hot, but not turn on the aux fan. What happens is with diminished flow, what coolant does get thru is cool, because it's going thru slowly, but since it's cool, the switch doesn't turn the fan on. But there's not enough cool water to cool the engine.

Replacement radiators are available, though not inexpensive. Depending on your desire for originality, E36 radiators have been used on E28s, not to mention E28 radiators will fit, with a bit of work. E28 rads are not as expensive and E36 can be found cheap.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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