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Can anyone help me figure out what this relay/wiring group is for?

amongmany

NAXJA Forum User
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Did the H4 headlight/harness upgrade this morning and in the process, discovered another group of wires/relay already installed. They're not headlight related —*I'm thinking perhaps they have something to do with the aftermarket head unit?

Pics are here: https://imgur.com/a/gxFaKFT

There's a relay with a group of wires:
The yellow wire goes from the relay/harness through the firewall.
The green wire is connected to something next to the engine (starter?)
Two wires (orange and blue) look like they used to be spliced and have subsequently been clipped.
The red wire has a connected attached to nothing.
One black wire has a connector attached to nothing.
The other black wire ends in a small antenna(?)
 
What you are calling an antenna looks more like a thermocouple. Might have been a left over wiring from a previously installed electric fan controller.
 
It looks to me like an aftermarket radiator fan controller, but for some reason it's tied into the A/C compressor clutch wire which makes no sense to me.

I was told by the PO that the radiator has been updated so that may be on the right track. No idea why it was wired the way that it is (not claiming it's right or wrong; I'm not an electrical guru and this is my first XJ).
 
Did a little more digging for you. Looks like a Hayden 3647 fan controller and it's complete. From the Hayden website you can download the original installation manual.

https://www.haydenauto.com/Installation-Instruction Sheets/Content.aspx

Here is a simple wiring diagram that shows how it most likely was wired minus the 80 amp relay and Taurus fan.

The yellow wire going into the cabin is +12v most likely switched on with the key.

electric-fan-wiring-with-a-c-elegant-hayden-imperial-vs-taurus-e-fans-my-review-page-3-s-10-forum-of-electric-fan-wiring-with-a-c.jpg
 
Did a little more digging for you. Looks like a Hayden 3647 fan controller and it's complete. From the Hayden website you can download the original installation manual.

https://www.haydenauto.com/Installation-Instruction Sheets/Content.aspx

Here is a simple wiring diagram that shows how it most likely was wired minus the 80 amp relay and Taurus fan.

The yellow wire going into the cabin is +12v most likely switched on with the key.

electric-fan-wiring-with-a-c-elegant-hayden-imperial-vs-taurus-e-fans-my-review-page-3-s-10-forum-of-electric-fan-wiring-with-a-c.jpg

Thank you! I'll have to take a closer look. That said, it appears that my install may still not be correct? I'll have to read through the install manual in detail, but should the temp sensor just be floating around under the hood like that? And I assume the ground wire (at least) should be connected?
 
Thank you! I'll have to take a closer look. That said, it appears that my install may still not be correct? I'll have to read through the install manual in detail, but should the temp sensor just be floating around under the hood like that? And I assume the ground wire (at least) should be connected?


You're install was disconnected, except for knowing where the yellow wire lands beyond the firewall. The green wire tapped into the A/C compressor is still connected. The temp sensor was probably stabbed into the radiator.
 
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