M-Class (W163) Produced 1998-2005: ML 230, ML 320, ML 350, ML 400 CDI, ML 430, ML 500, ML 270 CDI

ML 500 lift gate

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Sep 20, 2013 | 05:17 PM
  #1  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
ML 500 lift gate

Was having a problem with liftgate not colsing, i.e., Hatch door lock (bottom of rear tailgate) was stuck in locked position and tailgate won't close (lock). I was able to get the lock to the open position, using a screw driver, and was in the process of removing door trim to access actuator. Well, the liftgate closed and now I can't get it open. Any way to open the liftgate manually?
Reply
Old Sep 20, 2013 | 06:08 PM
  #2  
Maj. Dundee's Avatar
MBWorld Fanatic!
 
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Now you have to remove the interior tailgate panel. Refer to the below link for removal instructions.

https://mbworld.org/forums/4941206-post5.html
Reply
Old Sep 28, 2013 | 09:38 AM
  #3  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
Tailgate actuator

Well... purchased actuator/handle assembly from Mercedes. According to vin#, part #A 163 740 07 93 is correct assembly for my '03 ML 500. Installed this morning..... doesn't work. Anybody have any history with this part? Maybe needs to be programed?

Thanks,
Reply
Old Sep 29, 2013 | 01:21 AM
  #4  
DrX's Avatar
DrX
Senior Member
 
Joined: Mar 2002
Posts: 282
Likes: 5
From: Brisbane, Australia
2002 ML320, 2003 A160
Check the tailgate unlock relay k15 in the engine bay fuse/relay box. Replace if necessary.
Reply
Old Sep 29, 2013 | 06:19 AM
  #5  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
tailgate actuator

Thanks for the info, already checked relay K15. Swapped with another that I know works, didn't help. There's a central locking relay too. Didn't check that one, that might have something to do with my problem??? I'll check it today.
Reply
Old Sep 29, 2013 | 06:08 PM
  #6  
DrX's Avatar
DrX
Senior Member
 
Joined: Mar 2002
Posts: 282
Likes: 5
From: Brisbane, Australia
2002 ML320, 2003 A160
What exactly do you mean by "doesn't work"? Does it open and close? Can you unlock it manually, using the inside handle switch?

If the other doors lock, then the CL relay k20 is OK.
Reply
Old Sep 30, 2013 | 05:04 AM
  #7  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
Tailgate

The tailgate will open manually using outside handle & it will close shut. It will not lock using remote or centeral lock switch. Other doors will lock / unlock using either centeral lock or remote. No sound (actuator cycling) is coming from tailgate. It's like it is not connected, yes.... it is installed correctly and the two wires are pluged into correct cennections.
I wonder if the system may have to be resynchronized with new actuator?
Didn't have a chance to check centeral lock relay..... I thought a relay isn't like a fuse, a fuse is good or bad, no gray area. A relay doesn't work that way.

Thanks...
Reply
Old Sep 30, 2013 | 07:21 AM
  #8  
DrX's Avatar
DrX
Senior Member
 
Joined: Mar 2002
Posts: 282
Likes: 5
From: Brisbane, Australia
2002 ML320, 2003 A160
Time to study the wiring diagram -> wiring-diagram-central-locking-cl-.pdf

Your doors lock, so relay k20 is good. That same relay locks the tailgate - no sound or movement there during locking means you have an open circuit in the tailgate lock actuator circuit. It only takes one break to cause this, anywhere between F1, X18/1, M14/7, and back through X18/1 to F1 and relay k15. The most likely places are the moving parts - k15 (which you haven't clearly established is good) and where the wires pass between the roof and the tailgate. Repeated wear could rub through the insulation or cause breakage. A corroded connector is less likely.
Attached Files

Last edited by DrX; Oct 1, 2013 at 07:16 PM.
Reply
MB World Stories

The Best of Mercedes & AMG

story-0

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-1

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-2

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-3

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-4

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

 Verdad Gallardo
story-5

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

 Verdad Gallardo
story-6

Mercedes EQS Gets A Major Update: Everything You Need to Know

 Verdad Gallardo
story-7

5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

 Verdad Gallardo
story-8

Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

 Verdad Gallardo
story-9

10 Most Reliable Mercedes-Benz Models You Can Buy Used

 Verdad Gallardo
Old Sep 30, 2013 | 06:26 PM
  #9  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
Thanks.....
Reply
Old Oct 1, 2013 | 06:24 AM
  #10  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
tailgate relay K15

I went to two auto parts stores last evening for K15 relay, neither had the correct item. Going to MB dealer today for relay.

Note: During this episode with tailgate, I've had the cargo compartment lamp shut off because auotmatic control feature stopped working, lamp would stay on continuously. I switched back to auto control position last evening, to check if that feature is operating since replacing actuator/handle assembly. It isn't, lamp remains on & is not switched on & off by opening or closing the liftgate.

Thanks...
Reply
Old Oct 1, 2013 | 09:02 PM
  #11  
DrX's Avatar
DrX
Senior Member
 
Joined: Mar 2002
Posts: 282
Likes: 5
From: Brisbane, Australia
2002 ML320, 2003 A160
You have a fault with the tailgate rotary tumbler switch/circuit, that tells the AAM that the tailgate is closed. It's labelled S88/1 in the wiring diagram and for your model I think it's part of the lock assembly p/n 163 740 02 35. The connector has brown & white wires - if you short out the connector, that should turn off the lamp. Then you need to replace the lock.

If you ground the grey wire from the handle assembly, you can test that the actuator is working.

Last edited by DrX; Oct 1, 2013 at 09:42 PM.
Reply
Old Oct 2, 2013 | 05:23 AM
  #12  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
tailgate

Thanks for your help. Seems like the lock assembly may have been the problem all along. I'll check it as you suggest asap (probably this weekend). I'll let you know the results.

Thanks again...
Reply
Old Oct 2, 2013 | 02:59 PM
  #13  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
Tailgate

Well... "shorted out" the lock assembly & the lamp went out. So, looks like that is the problem. I guess the lock assembly being bad would cause the actuator not to operate?
The story of my life... I always start replacing the hardest to get to and most expensive part, if that doesn't correct the problem, work down from there.

Thank you....
Reply
Old Oct 2, 2013 | 08:59 PM
  #14  
DrX's Avatar
DrX
Senior Member
 
Joined: Mar 2002
Posts: 282
Likes: 5
From: Brisbane, Australia
2002 ML320, 2003 A160
Applying Occam's razor, you only need to replace the lock assembly. The tailgate actuator can't lock it because it's not properly closed. That would explain the lack of sound on locking. You can assume that relay k15 and the circuit is OK for now.

In hindsight, your initial description was that of a faulty lock.
Reply
Old Oct 3, 2013 | 05:17 AM
  #15  
ML 500 mz's Avatar
Thread Starter
Member
 
Joined: Jan 2011
Posts: 83
Likes: 0
From: Glenmoore, Pa
2003 ML 500
Tailgate

I'll order lock assembly today, and keep you posted.
Your knowlege & advice is appreciated.... Thank you
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 02:08 AM.

story-0
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9
10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE