Liftgate no longer working
Thread Starter
Junior Member
Joined: Apr 2019
Posts: 34
Likes: 1
ML 320 CDI, 2007
Liftgate no longer working
Our 2007 ML 320 CDI ceased to open or close the tailgate.
I found a very typical fault: Water at the bottom of the trunk and a broken wire coming to the solenoid.
I soldered a short length of wire to the connector and checked that there was a connection between the end of the wire and the connector pin. Then I connected the wire coming from the original wiring harness to the connector. The connector was clean inside - no corrosion. I also added a little more oil so that when the pump is in the upright position, the oil level is about 60% of the tank volume.
Despite repairing a clear fault, the liftgate still does not work. The lock opens and the pump is audibly running, but the door does not open or close. I guess the solenoid doesn't have a fuse of its own?
What could I try next? I have tried resetting the door (the door full up, pulling up the switch in the front door for 5s) - no help. Haven't measured if there is voltage at the solenoid terminals if I push the liftgate switch. I have access to a Delphi scan tool - could that reveal anything?
A new connector could be found (#282190-1 or #282190-1-pt, which also includes wires). The connector at least looks the same and the dimensions (height 17.5mm, width 23mm) seem right.
I found a very typical fault: Water at the bottom of the trunk and a broken wire coming to the solenoid.
I soldered a short length of wire to the connector and checked that there was a connection between the end of the wire and the connector pin. Then I connected the wire coming from the original wiring harness to the connector. The connector was clean inside - no corrosion. I also added a little more oil so that when the pump is in the upright position, the oil level is about 60% of the tank volume.
Despite repairing a clear fault, the liftgate still does not work. The lock opens and the pump is audibly running, but the door does not open or close. I guess the solenoid doesn't have a fuse of its own?
What could I try next? I have tried resetting the door (the door full up, pulling up the switch in the front door for 5s) - no help. Haven't measured if there is voltage at the solenoid terminals if I push the liftgate switch. I have access to a Delphi scan tool - could that reveal anything?
A new connector could be found (#282190-1 or #282190-1-pt, which also includes wires). The connector at least looks the same and the dimensions (height 17.5mm, width 23mm) seem right.
Thread Starter
Junior Member
Joined: Apr 2019
Posts: 34
Likes: 1
ML 320 CDI, 2007
I found the fault.
The purple connector, which clips on the plastic pump casing, was severely corroded. Hence upon disconnecting the connector, the solenoid ground prong had broken inside the slot in the male part of the connector. I managed to pull it out using tweezers.
The solenoid is supplied with continuous +12V, and the control box delivers ground when needed.
I need to find a new connector.... or replace both sides of the connector to a different one.
The purple connector, which clips on the plastic pump casing, was severely corroded. Hence upon disconnecting the connector, the solenoid ground prong had broken inside the slot in the male part of the connector. I managed to pull it out using tweezers.
The solenoid is supplied with continuous +12V, and the control box delivers ground when needed.
I need to find a new connector.... or replace both sides of the connector to a different one.
Last edited by Mika Riikonen; Apr 9, 2019 at 12:05 PM.
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
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From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
If the problem is is at the end of the lead harness, then yes the housing and pins (Green) are available.
But if the problem is at the pomp (Red), then no, the entire pump must be purchased.
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Thread Starter
Junior Member
Joined: Apr 2019
Posts: 34
Likes: 1
ML 320 CDI, 2007
Oh sorry - I had two faults there. The obvious and visible fault described in #1, and the hidden fault (#3) which occurred upon disconnecting the connector. I would be inclined to believe that the hidden fault is not happening unless one disconnects the connector.
The visible fault seems to be quite typical - so start with that one first.
The hidden fault was repaired by purchasing the parts mentioned in later postings. Of course, one can cut the wires from OEM connectors and reconnect them using any universal connector.
The lift gate has been working okay.
The visible fault seems to be quite typical - so start with that one first.
The hidden fault was repaired by purchasing the parts mentioned in later postings. Of course, one can cut the wires from OEM connectors and reconnect them using any universal connector.
The lift gate has been working okay.
