Started from me loosing my radiator during the Inspection

Changed the radiator and noticed that the engine temperature is very high. STarted monitoring front fans and they never kicked in. Tested the fans with 12V and they started going normally.

I decided to replace AC Cooling sensor (right behind the radiator) took the coolant out placed the new sensor, filled the coolant - AC works, fan does not.

It looks like car is trying to start the fan (I can sometimes physically see that fan is trying to start [small motion]) but nothing happens. I tried to rotate it with hand during the startup pulse and it worked, wondering if anyone has any ideas or had the same problem.

From my understanding it is the motor on the fan, but I'm wondering if there is some kind of relay thay turns on the front FAN that could of go bad.

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AlexS

First, as you probably know it's a single motor, which drives the other fan with a thin belt. You should be able to turn the left fan hub and both fans should turn freely.

There is a fan control module, it's in the front of the left wheel house, under the left headlight (need to remove the wheel house shroud to access the module.

I've had either the module or the motor cause this problem.

Gilly

Try depressing both AUTO buttons (at the same time) for 10-15 seconds & then see if the fans come on.
The fan control unit(N65) on that car should be in the fuse box.

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I hate to argue about it, but I'm really sure that N65 is where I stated it is, kind of "inside" the bumper under the left headlight.
This is a 97 210 chassis, replaced lot's of them.

Gilly

Just to let everybody know ... it was the front fan itself.
After replacing the part with the motor everything started working fine.

When we did a 12 v test on the motor it did work, but apparently didn't get to the full speed, however car could not start it at all.
After the replacement everything is working.

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AlexS

Could you tell me what it took to replace the fan motor?...besides money ..
I have a 97 E320. The fan will bind up. I can rotate it free and it will run with a clanking sound..as if it has roller bearings with one or two missing. Then it binds again.
Is it necessary to remove the radiator etc.?

Jeff

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Jeff

97 E320, ours 217,000miles
91 190E 2.6 daily driver 242,000miles
74 MGB,mine 120,000?
2006 BE350/Proline 21, 50 hours

Gilly -

In this particular model - '97 E420 - aux cooling fan activation is controlled by a pulse module (210 545 02 32), which is located in the engine compartment fuse box. Module function encompasses traction system, HCS, ATA and AAC. There is no frame rail-mounted aux cooling fan module for this vehicle.

I'm sure we have different engines

But this is what I have
a) Single main fan inside the engine that is sitting on the fan clutch * not electrical fan

b) Two aux fans sitting in front of the radiator (electrical)
Only one aux fan has motor (that went bad), the second aux fan is rotated by the first one via small belt

I had to order only a single aux fan with motor.
We did not have to remove the radiator, as far as I remember we only pulled the console with 2 front fans out, replaced the fan with the motor and placed everything back (1 hour procedure). I think that fan was couple of hundred $$

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AlexS