Temp sensors

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Doppleganger

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Having a blonde moment......I have a temp sensor for the new gauge but need one for the electric fans. Can I install a second one just like it or is it different?

Thx
 

WP29P4A

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When I had the electric fans on the Charger, it used a separate sensor that connected to the relay/controller, that was adjustable for temp.
 
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R Carnella

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I used a three wire temp sensor, basically a duel output. One signal to pcm other for Gauge.
 

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Doppleganger

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I've got ports in both heads for a temp sensor....one is going to the gauge - the other would be near the relays for the fans so thought I'd put one there also.

What temp does your fans come on?
 

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I used a three wire temp sensor, basically a duel output. One signal to pcm other for Gauge.


Those are handy. The earlier ones used in the 3x00 v6's were standard npt thread too.
 

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Having a blonde moment......I have a temp sensor for the new gauge but need one for the electric fans. Can I install a second one just like it or is it different?

Thx
No, you need a temperature sensor switch. This will run full voltage to your relay. The gauge sensor has a resistance to match the gauge. If you don't have a PCM running your engine, you need an older sensor. The PCM sends a 5 volt signal to it's temp sensor, reads what comes back. This will not power a relay. The PCM switches 12 volt power to the fan relay.

Many earlier systems had the sensor/switch in the radiator. They would be a lower temp than one used in the cylinder head.
 

Doppleganger

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No, you need a temperature sensor switch. This will run full voltage to your relay. The gauge sensor has a resistance to match the gauge. If you don't have a PCM running your engine, you need an older sensor. The PCM sends a 5 volt signal to it's temp sensor, reads what comes back. This will not power a relay. The PCM switches 12 volt power to the fan relay.

Many earlier systems had the sensor/switch in the radiator. They would be a lower temp than one used in the cylinder head.
Its EFI so does have a PCM. How it operates that - dunno - haven't gotten that far yet. lol
 

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