Aux Fan

[blatant]

Update for anyone searching on how to wire a 6 cylinder aux fan after a swap.

So if you review the ETM (97 318ti + 97 e36 m3)for the m44 it shows the two step temperature switch low speed goes through the DME via x20 pins 3 + 8 (late model TI) and then it triggers the low speed relay.
On the 6 cylinder e36 cars the temperature switch does not go through the DME but directly to the low speed relay.

When I did a test and bridged the two pins on the body harness side and jumped the low side on the temp switch, the fan turns on. So in conclusion, I will be tieing pins 3 + 8 on the body side together to bypass the x20 and directly trigger the low speed relay.

The high speed relay is wired the same way on both m44 + 6 cylinder cars, so that was already operational.

Last night me and my roommate (already went through his e30 swap) went through it and came up with that.

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Hi all,
Finishing up my s52 318 ti swap and have installed the 6 cylinder pusher aux fan. I have purchased Jim's manual and have searched the forum for tips or a DIY on how to wire the aux fan appropriately to run with the rad temp sensor + a/c on but have come up short.

Could someone point me in the right direction with a link or description on how to use the 6 cylinder aux fan ?

I would appreciate the help

[wake74]

At least on my 95ti, I just wired it directly back to the stock ti fan wiring including the relays and temp sensor. I used a mechanical fan too, belt and suspenders I guess.

[blatant]

I plan on running the mechanical fan for now. I plugged in the 6 cylinder fan to my 97 TI body harness and it will not work. I remember reading in the manual + several places online that additional wiring is required to make it operate like stock.

I was wondering if anyone knew what was required?

[blatant]

Just reading through the etms for both cars. I see on the ti, it is #3 in the x20. Have to do some more research

[blatant]

Anyone else have some more info? I have not touched the body harness. Just plugged in the aux fan that came with the e36 m3 parts car to the aux fan body harness with no luck.

[blatant]

I guess the question is: Those that run the e36 coupe/sedan aux fan (pusher) on their TI, was it a direct plug and play?

If so, I may have to check what is up with my wiring.

[wake74]

Can't speak for everyone, but it was direct plug and play on my 95. I didn't change any wiring.

[blatant]

Weird, I know the stock fan worked with the m44. Not sure what changed since then.

[blatant]

So if you review the ETM for the m44 it shows the two step temperature switch low speed goes through the DME via x20 pins 3 + 8 and then it triggers the low speed relay.
On the 6 cylinder e36 cars the temperature switch does not go through the DME but directly to the low speed relay.

When I did a test and bridged the two pins on the body harness side and jumped the low side on the temp switch, the fan turns on. So in conclusion, I will be tieing pins 3 + 8 on the body side together to bypass the x20 and directly trigger the low speed relay.

The high speed relay is wired the same way on both m44 + 6 cylinder cars, so that was already operational.

Last night me and my roommate (already went through his e30 swap) went through it and came up with that.