|Message Title: Re: Auxiliary cooling fan testing|
|Posted by: Dudley Doright on 2002-01-10 at
(posted from: Host: IP: 18.104.22.168)
From: Alan Kenny AKenneyD@msn.com
Subject: To remove Pusher Fan
Hi Folks, It was not hard at all, First I checked "search" at roadfly.org, E39 and found archives under auxiliary
fan & under pusher fan.
Tools needed was a 1/4" ratchet, 8mm,10mm,13mm sockets, 8inch extention came in handy, a 3/8" ratchet and a T-45 (torks) socket bit, needlenose pliers,and a small pick to drive out the plastic push-ins.
First I used a 8mm sockets to remove the two headlight assembly's, the ext. came in handy for the
back bottom two, disc. the wire plugs and pull them forward having the center edge come first. Then in
the wheel wells, I removed the bottom two and the outter upper one, 8mm screws towards the front. Then use the pick to pull down the center pins that are located in the front lower grills, next to the fog lamps (up
under top side), pull down the center pin and the plugs will come out, then pull out the little grills and you can see the spot up under where the T-45 bit goes to remove the bumber, I put a piece of carpet down and it slid right out to unclip the fog light connectors, all the duct work slides out with the bumber assembly, now the rest is easy.
A 10mm socket to remove the air snorkel bolts, 13mm to loosen the fan frame assembly, and the three plastic push-ins that attach the shroud to the radiator frame I used the pick and pushed the small center pins, straight down and caught them at the bottom, the needlenose pliers came in handy to pull the lower left fan shroud push-in pins center out, and unplug the wire connector. My '98 540 Fan had 4 wires, tan (brown) was negative, black and a black with red stripe was low and (med.?) and the black with blue stripe was the high speed, which uses the two large wires. Next I Pull it off the car and cleaned out all the debris... alot of crud in mine, blocking good air flow and good fan operation.
I took the fan in and blew it out with air and spayed a little WD-40
in the holes in back and keeped playing with it with a 12 volt dc power
supply / battery with the negetive on the tan and the positive on the Black
with blue stripe.... slowly but surely it roared back to life...as
Did "Dudley Doright's" who's archive gave me the Idea of trying this
before spending the $360.00 US at my dealer!, just for the part!
I check the connector at the car and found 14 volts dc there across the tan and one of two smaller wires ( either the blk or the red striped one) with car running and the A/C on, so I figured that the relay and fuse was good, I then threw it back on, pluged in the wire connector and restarted the car up and turned on the A/C, with a little help at first, it started, and I let it run awhile to revive itself and I heard it go from low to high speed as the car heated up and back down to low again. I shut the car off and back on a few times and it was OK, I put it back together, COOL A/C AGAIN!
It takes an hour to remove, an hour (I spent) cleaning out the fan, condencer and radiator and an hour to put it back together. As stated by others before me and I'll agree that it is a good Idea to clean out this fan and area even if yours is still running, as preventitve maintenance!! Good Luck, AL 103Control
Message Title: Re: Electric Auxillary Pusher Fan Update
Posted by: Jim Cash on 2002-07-08 at 12:50:33
(posted from: Host: hse-montreal-ppp141224.sympatico.ca IP: 22.214.171.124)
Just some further info.
Yes jumpering at that rad temp sensor connector will allow you th check the operation of the fan.
By jumpering at that point you are operating the relays that provide the power
source to the fan. Relays are in the E box.
The low speed of the fan is obtained by passing the current through resisters located on the front of the fan housing. To get high speed the voltage is applied directly to the motor bypassing those resisters.
So failure to operate can be a relay, wiring, or resister problem as well as the fan motor.
There is another path to operate the low speed - input from the climate control unit to that relay circuit. But there is logic related to compressor opertion, compressor system pressure, and external temperature above 10C.
My info says that the high speed is activated "only" by the rad temp sensor going above 99C. So do not expect the A/C system to activate the high speed of this fan.
And - I think there have been about 6 versions of this fan and circuit. In
98 there was a change in May and again in Sept.
Sometime in 98 or 99 they changed from the 2 speed fan to a variable speed which as more smarts behind it's operation - so diagnosing operatin is more complex on those - I don't have those details.