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Mike S.
Mike S., ASE Certified Technician
Category: Ford
Satisfied Customers: 7568
Experience:  ASE Certified Master Technician
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Ford F150: I have a 1987 ford F150, 302 engine. The temperature

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I have a 1987 ford F150, 302 engine. The temperature gauge is not working. I pulled the gauge cluster and unplugged the harness that goes to the temperature gauge I need to identify the wire that goes to the temperature gauge so that I can splice into the wire and run the wire directly to the temperature sending unit. I do not want to add an aftermarket temperature gauge. I want to use the original temperature gauge in the instrument cluster which is why I want to splice into the wire in the harness that plugs into the back of the instrument cluster.

I966Charger :

Hi, my name is XXXXX XXXXX I will try to help you with this tonight


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I966Charger :

Do you know where the temperature sending unit is on this?


 

Customer:

Well I think it is on the driver side of the engine towards the front of the engine. Is this correct?

I966Charger :

Yes,near the thermostat to check it you just unplug it and ground the lead it should go full "Hot"


 

Customer:

Well part of the problem is that there is no wire to the temperature sending unit to unplug. This is why I need to run a wire to the unit directly from the connector harness plugged into the back of the instrument cluster.

Customer:

Sorry I meant to say run a wire from the harness to the sending unit.

I966Charger :

So you have looked at a wiring diagram to find the color of the wire that is supposed to be going to the sender?


 

Customer:

Also, I want to go the the sending unit right. Not the coolant temperature sensor. The coolant temp sensor has no wires connected to it either.


 

Customer:

No I don't have a wiring diagram to look at.

I966Charger :

There are 2 sensors , 1 for the computer and another for the gauge


 

Customer:

the sensor for the computer is not hooked up at all. but right now I am trying to get the gauge in the dash to work.

I966Charger :

Hold on and I will send the diagram to you. The computer wants to know what is going on too


 

Customer:

The engine was replaced on this truck and some of the wires are missing and were never hooked up. The truck seems to run okay, but as you say, I suspect I also need to hook the coolant temp sensor.

I got one diagram, that shows the coolant sensor. Its a black/white wire from pin 23 of the electronic control assembly and the other wire is a light green/yellow to the pin 7.

graphic

Coolant temperature sending unit-5.0L

graphic

Is there only the one wire to the sending unit?

I cannot find a wiring diagram to show the one wire for that sender. There should be something near the sender coming out of the wiring harness with just the one wire plug, do you see it?
Customer: replied 5 years ago.

Thanks much! One more thing, I assume that the electronic control assembly is another word for the computer? If so where is the computer located (electronic control assembly)?

Sorry, I was out in the yard.

The Engine Control Computer is located:
Front seating area, driver side, under dash, mounted behind kick panel

Mike S., ASE Certified Technician
Category: Ford
Satisfied Customers: 7568
Experience: ASE Certified Master Technician
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