heat not working, does it get a signal from any computer in the car?

2004 MERCURY GRAND MARQUIS

53,487 MILES • 4.6L • V8 • 2WD

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The coolant in level, temperature goes normal and heater core hoses get hot, so not clogged up. i replaced the electronic climate controls and all the vacuum actuators are working but the electric one for the cold to hot blend door is not. i unplugged it without taking out the actuator and plugged a new one to make sure, before taking the dash out but the new isn't working either. Do they get a signal for any computer in the car?

Dec 18, 2023 at 8:22 AM

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The signal is produced by the HVAC controller which you said you replaced, but there are five fuses we need to check in the fuse panel below the left side of the dash. The fuses are # 23, 15, 16, 6 and 21. here is a guide to help you and the fuse locations. I also have included the HVAC system wiring diagrams so you can see how the system works.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Check out the images (below). Let us know how it goes.

Images (Click to enlarge)

Dec 18, 2023 at 4:33 PM