Year differences on engine harness and ECM.

Tech discussions on the L77 6.0L V8.
VintageIron41
Posts: 162
Joined: Sun Nov 18, 2018 2:23 am

Year differences on engine harness and ECM.

Post by VintageIron41 »

Hello and thanks for taking time to read this.

Does anyone know if there are differences in the engine harness and ECM on the Caprice PPV's from year to year?

Example, if the vehicle was a 2012 with high miles, and you knew of a 2017 L77 low miles that did not come with an engine wiring harness, what would it take to make the 2017 work with 2012 ECM and harness?

Thank you!
s/c'd cav
Posts: 1387
Joined: Mon May 30, 2016 3:12 am
Location: PHOENIX AZ

Re: Year differences on engine harness and ECM.

Post by s/c'd cav »

plug and play
VintageIron41
Posts: 162
Joined: Sun Nov 18, 2018 2:23 am

Re: Year differences on engine harness and ECM.

Post by VintageIron41 »

Again, thank you for your time taken to reply s/c'd cav, and thank you for the information.
s/c'd cav
Posts: 1387
Joined: Mon May 30, 2016 3:12 am
Location: PHOENIX AZ

Re: Year differences on engine harness and ECM.

Post by s/c'd cav »

you are welcome
smwalker
Administration Staff
Posts: 2204
Joined: Mon Jul 29, 2013 1:44 am
Location: Azusa,CA

Re: Year differences on engine harness and ECM.

Post by smwalker »

What you describe is just swapping out the L77 engine/trans. As long as you keep the same harness from your main car that is plug and play. BUt trying to use a 17 engine harness in a 12 chassis will not work at all. Electrical architecture changed in 14.

That also being said I am not sure all the connectors for sensors are the same in the WM to WN years on the engine, But that would be easy to correct by swapping out the sensors to the ones with the correct connector.

In other words do not get rid of your old engine as you might need to scavenge some sensors off it.
Steve Walker
Azusa, CA
'11 PPV 9C3 Huron White
VintageIron41
Posts: 162
Joined: Sun Nov 18, 2018 2:23 am

Re: Year differences on engine harness and ECM.

Post by VintageIron41 »

smwalker wrote:What you describe is just swapping out the L77 engine/trans. As long as you keep the same harness from your main car that is plug and play. BUt trying to use a 17 engine harness in a 12 chassis will not work at all. Electrical architecture changed in 14.

That also being said I am not sure all the connectors for sensors are the same in the WM to WN years on the engine, But that would be easy to correct by swapping out the sensors to the ones with the correct connector.

In other words do not get rid of your old engine as you might need to scavenge some sensors off it.
Thank you for the good advice!
VintageIron41
Posts: 162
Joined: Sun Nov 18, 2018 2:23 am

Re: Year differences on engine harness and ECM.

Post by VintageIron41 »

To who take time to read and reply with answers to this newbie to the Caprice PPV thank you!

Senior citizen former owner of a 1996 Caprice 9C1, a '94 Caprice wagon with the LT1, several Crown Vic' Interceptors and currently a 2012 Dodge Charger ex-Police. Mentioning that only to be clear that I know little about the Caprice PPV's particularly what parts, what years will interchange.

Per this thread, I have a lead on a 2012 roller PPV, the owner is keeping the engine harness. I also have a lead on a low mileage 2017 engine and transmission.

As smwalker pointed out, the harness ( ECM too? ) will not interface with the 2012 vehicle due to changes in 2014.

Question, if I were to acquire a harness and ECM from either a 2012-13, or purchase a new harness and ECM from GM parts supply, would that complete the above units as plug and play?

Thank you!
s/c'd cav
Posts: 1387
Joined: Mon May 30, 2016 3:12 am
Location: PHOENIX AZ

Re: Year differences on engine harness and ECM.

Post by s/c'd cav »

if that other motor has the harness , see if the guy selling the roller will swap harnesses with you , since he is obviously only keeping it for a engine swap

even when they are harnesses for swaps out there better than hacking up a stock harness , lol
VintageIron41
Posts: 162
Joined: Sun Nov 18, 2018 2:23 am

Re: Year differences on engine harness and ECM.

Post by VintageIron41 »

s/c'd cav wrote:if that other motor has the harness , see if the guy selling the roller will swap harnesses with you , since he is obviously only keeping it for a engine swap

even when they are harnesses for swaps out there better than hacking up a stock harness , lol
Thanks 2nd Cav, the roller owner is definitely keeping the the harness that came with his motor.
smwalker
Administration Staff
Posts: 2204
Joined: Mon Jul 29, 2013 1:44 am
Location: Azusa,CA

Re: Year differences on engine harness and ECM.

Post by smwalker »

You can get the harness by it's self, just got to dig deep in the wallet.

https://www.gmpartworld.com/oem-parts/g ... LWZsZXg%3D" onclick="window.open(this.href);return false;

THe parts circled in red are the important changes between the WM and WN harnesses. Those are the interface connectors in and around the fuse box.

Image

But now i am realizing something. We are just talking about the engine harness but the ECM is not necessarily part of the Engine harness it is either part of the chassis harness or a separate harness by it's self. SO if he is taking that also you may need just about every harness forward of the firewall. Find a part out situation for that.
Steve Walker
Azusa, CA
'11 PPV 9C3 Huron White
Post Reply