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Discussion Starter · #1 ·
I recently replaced both fans since they stopped working. I took the top radiator hose to remove the radiator fan. Some coolant drained out so I topped it off an bled the system. During the bleeding, when the fans turned on, it was both and the AC was off. The fans turned on at around 217 F per my code reader. That got my attention so I followed the troubleshooting steps in the service manual to find out why the radiator fan was not turning on alone.

Fuses and relays are OK. I get battery voltage and ground at the radiator fan switch plug. The radiator fan turns on when the jump the fan switch plug. Service manual points to a faulty radiator fan switch.

I ordered a new OEM radiator fan switch and a OEM thermostat. I replaced the thermostat since I was draining the coolant and working in the area. I tested both parts per the service manual before installing them, both work fine.

Fast forward about 3 weeks... I changed the switch and thermostat. When through the bleeding procedure and to my surprise, the new fan switch seems to make no difference. At around 214 F, both fans turned on (AC was off). I let them turn on again and topped of the radiator. I unplugged the fan switch, got some dust/dirt off the connector. Looks clean so I plugged it back in firmly. Ran the engine again and no change, both fans turn on at the same time.

I tested the old switch and it actually works.

Car is not overheating, temp is usually around 194 when driving. Tonight it was cooler so it stayed at around 190. Temp stays about the same when driving with the AC on or off.

The wiring to the fan switch tests OK and the new and old radiator fan switches work. I checked the connection and its clean. The coolant I got out of the radiator looks line new. I doubt it is a blocked radiator since the coolant is clean. I bled the system twice, once when I replaced the fans about 3 weeks ago and again today.

Question is, when is the radiator fan supposed to turn on alone? Has anyone seen that happen in their Element? I don't know if something is wrong or maybe I'm not checking the fans at the right time. Thanks.
 

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This is an example why people who work on their own vehicle should have the service manual. If you look at the description of operation for the cooling fan operation it will tell you both fans will turn on either by the radiator fan switch or by the ECM. A look at the wiring diagram will show that both fan relay coils are wired together in parallel so they can not run independently of each other.
 

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Discussion Starter · #3 ·
I saw that in the service manual. I also saw that the radiator fan should turn on when the radiator fan switch is between 199-203 F. I haven't seen the radiator fan turn on alone even though the engine coolant temperature (ETC) sensor, which is mounted on the engine head, reads in the 217 F range. At this point I'm led to believe that 217 F at the ETC sensor is less than 203 at the radiator fan switch.

Just for future reference, I unplugged the radiator ran switch and shorted the terminals. The fan turned on. I took my old radiator fan switch and heated it. I plugged it into the harness/plug and the fan turned on. That runes out a bad connection between the plug and the switch.
 

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I saw that in the service manual. I also saw that the radiator fan should turn on when the radiator fan switch is between 199-203 F. I haven't seen the radiator fan turn on alone even though the engine coolant temperature (ETC) sensor, which is mounted on the engine head, reads in the 217 F range. At this point I'm led to believe that 217 F at the ETC sensor is less than 203 at the radiator fan switch.

Just for future reference, I unplugged the radiator ran switch and shorted the terminals. The fan turned on. I took my old radiator fan switch and heated it. I plugged it into the harness/plug and the fan turned on. That runes out a bad connection between the plug and the switch.
I think you are chasing a problem which does not exist. First, the radiator fan will not turn on alone unless the condenser fan is dead. The coolant coming out of the engine going to the radiator will be at 195 degrees or more. The coolant temperature at the bottom of the radiator where the second temperature sensor is located will usually be 20 to 30 degrees cooler than the temperature at the radiator inlet. The actual coolant temperature at the engine coolant temperature sensor in the cylinder is the hottest location. The water outlet to the radiator will be less and the bottom of the radiator will be less still. Given that, the engine coolant temperature at the cylinder head can be as much as 230 degrees F before the cooling fans are turned on. Your testing shows the system is working.
 

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Discussion Starter · #5 ·
Makes sense. I didn't know that the coolant went into the radiator through the top hose and out through the bottom hose. Thanks for the help.
 
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