jgcable 0 Posted October 25, 2010 Was driving around for about 10 minutes when I stopped to talk to some friends. I was sitting in the car running for about 15 minutes when one of them noticed my car was leaking antifreeze. I opened the hood and it was just starting to spit out of the vent in the overflow tank. I noticed that the fan was not on. When thinking about it I haven't noticed the fan running when the car was turned off for the last week. I have only driven the car at night for about 10 miles total the entire week. So.. I umplugged the radiator fan switch and I jumped the wires. Red to Red/White.... NOTHING (I think this is supposed to be low speed) Red to Red/Black..... Fan works. Feels like high speed. Put on the AC...... Fan works. So, I traced the wires and noticed that its a a VERY small circuit between the fan, the fan switch, the relay and the battery. All the wires look fine. Very simple set up. So... I replaced the radiator fan relay... it had #53 on it. This relay is along side another relay and they are both bolted to the radiator shroud. I replaced the radiator fan switch. This is the switch that screws directly into the radiator. Fan still doesnt come on. I can't figure this out. Its so simple yet I can't get it to work. Temp gauge went up a little past 160 and the fan still didn't turn on. I was watching the radiator overflow tank and it was rising. It got a little past the max mark about 1/4" from the vent hole and I shut the car down. What the heck could I be missing??? It can't be the fuse under the dash because the fan works when the AC is turned on. I checked it anyway and its fine. Quote Share this post Link to post Share on other sites
jgcable 0 Posted October 25, 2010 Could a bad thermostat cause something like this??? My top radiator hose was very hot. Quote Share this post Link to post Share on other sites
volksworld13 0 Posted October 25, 2010 if your radiator is partially blocked, up not circulating well, the the rad switch will not get hot enough to actuate the fan. have you evere flushed and cleaned your cooling system since you have owned it? if you bridge the terminals on the switch and low, high will work when correctly bridged, it can only be a duff switch or its not getting hot enough. Quote Share this post Link to post Share on other sites
jgcable 0 Posted October 25, 2010 I pulled the plug on the radiator thermo switch. With the key in the OFF position.... Red to Red/White ..... nothing. This is supposed to be the low position. Red to Red/Black...... Fan turns on. This is the high position. Am I supposed to be doing this with the key in the on or off position? I have been checking it in the off position. Quote Share this post Link to post Share on other sites
jgcable 0 Posted October 25, 2010 When I put the AC on and the fan comes on is it low speed or high speed? Quote Share this post Link to post Share on other sites
jgcable 0 Posted October 26, 2010 Followed the Bentley manual and rechecked the fan. Both speeds work perfectly. I had grabbed a tutorial online and was checking the wires per the tutorial which was WRONG. Started motor, let it warm up until the temp gauge was reading 160. Fan never came on. I checked the upper radiator hose and it was soft and HOT, I checked the lower radiator hose and it was stone cold and HARD. Thats a stuck closed thermostat to me. Its not allowing hot coolant to flow through the radiator and that is why my new radiator thermo switch isn't turning the fan on. Quote Share this post Link to post Share on other sites
Tom Hem 10 Posted September 7, 2015 Followed the Bentley manual and rechecked the fan. Both speeds work perfectly. I had grabbed a tutorial online and was checking the wires per the tutorial which was WRONG. Started motor, let it warm up until the temp gauge was reading 160. Fan never came on. I checked the upper radiator hose and it was soft and HOT, I checked the lower radiator hose and it was stone cold and HARD. Thats a stuck closed thermostat to me. Its not allowing hot coolant to flow through the radiator and that is why my new radiator thermo switch isn't turning the fan on. did you get this fixed and if so how? as I have the same problem atm Quote Share this post Link to post Share on other sites