2007 Suburban powered Liftgate problem & fix

[Greaser007]

Good morning peeps.
Awhile back, the powered liftgate quit working on my wife's 2500 series Burb.

Her and I took it to our local Lithia Chevrolet dealer in Redding, Ca., and paid an $85.00 fee for a "professional" diagnostic.
End result of the diagnostic was estimate of $1,800.00 for replacement of:
1. Liftgate lift motor assembly.
2. Liftgate latch.
3. Liftgate struts.

Ok, I might be stupid, but my gut tells me only one problem is the cause.
So, I refused paying Lithia for an all inclusive repair.

Bear with me as I explain the sequence of my repair.
I began internet research and wound up in these forums with having found an earlier thread where another 'victim' had a similar problem, and wound up changing pieces and parts until he ordered an OEM Latch assembly.
Please see attached link below:

Liftgate Latch, Motor or Module? How to know which?

Folks: I have another thread where I asked for general help diagnosing my lifgate issues. I thought I'd reach out in a different thread to see if anyone can help me--and possibly others--with the process to properly diagnose the issue. From what I can tell, we have 3 major components in...

www.tahoeyukonforum.com

@Mr T first replaced the components with parts from Amazon, and all worked for awhile until the liftgate quit. Next time around, he purchased an OEM latch and Presto, all was good in the world.

I searched YouTube for information and explanation of how the liftgate components communicate, and only found an explanation of how to drill a hole thru the plastic liftgate inside cover to then manually push a small latch with a screwdriver to open the liftgate. Ugh
Below link from Dorman Products shows how to remove plastic interior panels to expose the Liftgate lift motor assembly:

I could not find a wiring schematic either, so I dove in head first.
Removing the plastic interior driver's side panel must be done to access the liftgate lift-motor assembly, which houses the Liftgate Module.


Below is a YouTube link for Liftgate plastic panel removal:

Moving forward, removing the plastics is a real PIA so take your time.

I am going to save this and resume upon saving. Bear with me.

As per the above video, I disassembled the Liftgate lift motor drive assembly and electrically checked the operation of the clutch assembly, and when putting 12v to the clutch solenoid, it was working properly.
The gear teeth and all looked brand new for a 15-year old mechanism. I re-assembled the motor-drive.
I know nothing about how to check the module, so i again followed my gut and focused on the Latch mechanism.
Replacement latch link below:

More Information for GM GENUINE 84243380

I logged onto RockAuto and ordered a new OEM Latch.
GM GENUINE 84243380
Once the new latch was installed, everything worked as normal.

I disassembled the latch mechanism to see what kind of limiting switches and stuff are involved. it's involved !

 

[Greaser007]

Hi all, Greaser007 here again to attempt with attaching a few photos of the Latch mechanism.


above photo showing the inside of the latch assembly.
if you look closely you will see two small switches which are part of how the latch communicates with the Module and Liftgate motor.


Another photo of insides of the latch assembly, and another switch with blue seal.
Believe me, this is a very complicated and involved assembly of which I don't think I'd ever be able to fix.


Above showing swedged pivot heads ground off and plate removed (cost me some blood) showing the innards of the latch mechanism.


Above photo showing (at pencil tip) the mechanical latch release to push on with a screwdriver to manually unlatch the powered Liftfate Hatch.


Above photo showing mechanical latch accessed from inside the vehicle through a hole which must be drilled through the inside plastic panel on Liftgate hatch.
This also shows some of the internal mechanism.

I hope this write-up helps someone else !

Important note here:
Electrical switches contact points become corroded and compromised upon umpteen closures and Fail.
I'm not a pro mechanic, but I have found that Relay's go bad because the contact points become corroded from sparking over time, and if the points are cleaned, they function again like new.
The latch assembly is so dang complicated, just go buy a new one and install it yourself. I did and saved $1,400.

With the $1.400.00 saved I purchased a new set of four BF Goodrich mud terrain tires for my Jeep. hahaha

A little sweat eaquity never hurt an ambitious guy.

 

[97YukonNZ]

Nice work!
Thanks fir the contribution!
And welcome to the Forum from
New Zealand

 

[Miami-Dade]

Welcome from Miami Beach!
I agree nice work!

 

[Geotrash]

Nice! I just went through this process on my '07 and did end up replacing the motor gear, the latch and the struts. The struts failed within weeks after fixing the latch and I had replaced them only 3 years before. Se la vie. It's a complex system but overall quite reliable, I find.

 

[Joseph Garcia]

Thank you for posting your repair experience. Much appreciated. Our collective knowledge base in this Forum has been increased.

 

[m1dn]

Thank you for this!
Ordered same actuator few days ago, replacing when it comes next week.
Hopefully resolves my issue as well

 

[m1dn]

Got the part finally, ordered from US Amazon for ~60$.
Took about 20 minutes to replace, runs smooth now, let's see how long the Actuator made from Chinesium lasts!

 

[Yukon XL 300k]

I just had the same issue with my 2007 Yukon XL. Codes were showing two latch errors. I decided to replace the hands free closing module (25889603) $333 OEM from Amazon, the latch (84243380) $216 OEM from Amazon and the struts, $100 from the local dealer. So for under $650 the parts back there are all new OEM parts. As good as new and saved $$$ over the $1500 dealer quote!

 

[Geotrash]

I should add that I used the Dorman actuator gear assembly and a knockoff latch assembly. Knock on wood, but 2 years later and thousands of uses, and all still seems to be well.