Upgraded SYNC1 4" to SYNC 3.4 8", No heat or AC and can't reset HVAC Module

Ford AsBuilt
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1

So I decided to upgrade my 2014 Ford Explorer Base. It came with a SYN1 4” screen and I am upgrading it to a SYNC3 8” screen. I sourced out all the parts either online or from used part shops nearby.

New parts I acquired for the update:

APIM and 8” Screen from 2019

Wiring Harness 4” to 8”, Sync1 to 3 from Amazon

HVAC Module GB5T-18C612-BG

New USB wire & USB Plug and bracket for SYNC3

New GPS antenna, gives error when turned on but works for NAV

2011 FCIM 8” opening and dual HVAC controls

HD Radio receiver

I successfully installed everything and was able to update the SYNC to 3.4

What works:

HD Radio, Bluetooth, phone and Pandora App etc.

NAV – volume lowers but don’t hear voice commands

SYNC button and volume controls on Steering

What doesn’t work:

HVAC, The buttons light up and the corresponding buttons on the screen are matched, but no heat or AC.

I am new to forscan but I tried my best to get it corrected. I have read lots of other posts but can’t get it right.

When I use Forscan it says HVAC module can’t read DTCs and I it won’t reset. I think it doesn’t even see the new HVAC module.

I did take the whole thing out put the 4” system back just to make sure it’s not a blown fuse or HVAC hardware issue and it worked fine with all the factory parts. It did not work with just the new HVAC module.

I really need AC and heat. I have come this far and don’t want to go back to the 4”. The Sync3 looks amazing. I hope someone can help.

I have attached the APIM as Build.

APIM AS BUILT
APIM AS BUILT1530×1445 271 KB

HVAC REBOOT
HVAC REBOOT1427×675 86.1 KB

Thanks,

2

Why did you change the HVAC module? Put the old one back in.

4

I changed it because my car is a base model and had Sync 1, The HVAC wasn’t working so I ordered the new module from ebay as it was for automaic climate control. I can easily put the old one back in, but I don’t know what I need to get it to work.

So I did order another harness(different brand) from Amazon and will try it tomorrow but it looks the same.

any suggestions?

5

You will never get Automatic HVAC controls working. There is actually a physical differance with the HVAC unit that you would have to pull the whole dash to change. The HVAC should work fine with the old module in there. You will need to make sure the APIM knows it is not Dual temp in the AB.

Hopefully the new harness works but we have seen some wiring issues with them.

6

When I had the old HVAC module in it just blew hot air constantly, I guess as a default for those in Alaska to not freeze. But in Florida we were melting.
What lines should I change in the AB?

Also I originally bought a 2016 non-Sony FCIM but the plugs were different. The non-Sony FCIM I have now is from a 2011 and the plugs matched but do ai need a 2014?

7

You cannot use a CEGA 1.3 2016+ FCIM in a CGEA 1.2 11-15 Explorer. They have different networks and the HVAC module will not communicate properly going into default mode only blowing hot air. There was nothing wrong with the old HVAC module it was just in default mode due to the incompatable FCIM. Sony or not dies not matter as long as it is from a 2011-15 Explorer.

For the HVAC module or APIM? This is all that needs to be changed in the HVAC module if it is not already. Should be set to 2.

image
image343×310 9.08 KB

8

So I put the original HVAC module and when I do a new vehicle profile scan it does not show the HVAC module. I know I did not brick the module because it works with the 4” set up.

I think the wiring harness is the issue. I tried a second harness and got the same results. I can’t see the module so I can’t program or reset it.

I can order a different harness, I prefer Amazon as I have Prime and it’s quick delivery and easy returns.
Any suggestions what harness to order from Amazon or eBay if that’s where to get it?

Also the 12 pin plug that was plugged into the back of the 4” screen doesn’t have anywhere to plug into with the harness I bought. Should it have an adapter to plug into? or is it okay left unplugged?

no HVAC module recognized
no HVAC module recognized1920×2039 675 KB

9

You need that 12 pin plugged in as the harness is going to use that to pull the canbus signals off of it that it cant get from the ACM plug. Sounds like it’s the wrong harness if it does not have a plug for that 12 pin.

I have no recommendationsa as I do not use them and I just wire it all myself like OEM.

10

Thanks for the quick reply and sage advice. I think my Hardware is good, just have to figure out the wiring harness. I’m not in rush as I want to get it right. I’ll keep you posted.

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