SL55/63/65/R230 AMG Engine / radiator / suction fan troubleshoot

Jul 2, 2013 | 02:48 PM

FLGSHP7

Thread Starter

Junior Member

Joined: Sep 2012

Posts: 42

Likes: 0

From: Central, IL

SL500

Engine / radiator / suction fan troubleshoot

So my engine fan stopped working. I pulled the fan out and it looked fine and the motor seemed to be in good condition. Reinstalled and started playing with relays in drivers side fuse box(K40/2) and voila! It works. Well sorta. Now whenever I'm running AC the fan comes on but when AC is off, its a brick. Is this a coolant temp sensor? Anyone else had similar problems? TIA

P.S. I bought an extra used fan off ebay to help troubleshoot before i checked relays. Got it for a good price so its nice to have a spare around. I have had both fans in the car, same results.

Jul 2, 2013 | 07:40 PM

alx

MBWorld Fanatic!

Joined: Dec 2004

Posts: 4,268

Likes: 253

Temperature activation is broken somewhere. The fan is coded to turn on with ac so that is why it works when you turn ac on.

Activate fan with das and follow the troubleshooting decision tree.