My Phaeton is equipped with the power opening and closing trunk lid (production code 4E7). This is a nifty little option that raises and lowers the trunk lid hydraulically when the drivers presses the appropriate button on the car. My wife likes it, because she is kind of short and this makes it easier to close the trunk lid.
Anyway - this gadget stopped working a few weeks ago. It kind of died a slow death - at first, the power open and close function became intermittent but we could still operate the trunk lid manually, and eventually, the whole thing died, which meant that the electrically operated trunk latch would not engage when the trunk lid was closed. Although the lid stayed in the closed position, the annunciator light in the instrument panel was always on, indicating that the latch was not engaged.
I dropped by my VW dealer to ask for some help, and they did a diagnostic scan of my Phaeton. This returned a fault code stored in the J605 Trunk Lid Control Module, which is a slave controller to the J393 Central Control Module for the Comfort System (you can see the Phaeton convenience system network topology at this post: Convenience System Controllers). The fault code stored was "00317 - Rear Lid Control Module (J605) 014 - Defective", which was pretty definitive. So, the Phaeton technician at my VW dealer ordered a new control module. It showed up 3 days later, and he sent me an email inviting me to drop by whenever I wanted, because it would not take very long to replace this part.
He was kind enough to allow me to take some pictures of the part and the disassembly process, here they are, in step by step format, in case anyone has a similar problem in the future.
1) Lower the big panel in the 'roof' of the trunk compartment, to allow you to get access to all the electronic controllers.
This panel is held in place by 9 Torx head screws. 7 of the screws are around the perimeter of the panel, 2 are located in the middle of the panel. The screws are all covered with a black flock finish, to match the panel, and finding the screws is a bit like looking for a black cat in a coal mine at night. You need quite a bright worklight to find them.
When you have all the screws removed, the panel will lower. It is hinged at its forward edge.
![Image]()
2) Remove and replace the controller module.
This is very quick and easy, it is 'plug and play'. Like most other control modules in the Phaeton, it is easiest to remove the electrical connector first, then physically remove the module. When installing the new module, put it in place first, then plug it in second.
The first hint we had that things were going well was when the trunk lights illuminated as soon as the new controller was installed. It seems that operation of the trunk lights, as well as latch operation, raising and lowering the trunk lid, and pinch protection are all controlled from the J605 module.
![Image]()
3) Adapt the new module, so it knows the position of the trunk lid when it is fully open and fully closed.
Most controller modules in the Phaeton need to be 'adapted' whenever a new control module is installed. Adaptation is the process of familiarizing the module with the signals coming from the components that it controls, so that it can properly operate them. It's exactly the same process as what you do when you set new tire pressures in your TPMS - what you are doing is 'adapting' the TPMS to the new pressures, so it knows what the acceptable range is.
To adapt the J605 module, open address 46 (the J393 Central Control Module for the Comfort System), select function 10, adaptation, and go to channel 22. Close the trunk lid (it won't latch, but put it in the fully closed position) and then re-enter 0 (zero) as the adaptation value. Next, move the trunk lid to the fully open position, go to channel 23, and re-enter 0 (zero) as the adaptation value. Now you have defined the extreme limits of movement of the trunk lid, and the new module will work perfectly.
It is important to note that the new module will not work at all unless you adapt it. This is not mentioned in the Phaeton service manual, because it is assumed to be common knowledge for every control module. Also, note that you cannot directly address the J605 module, because it is a slave to the J393. This is why you open the J393 controller (address 46) when you want to adapt the trunk lid control module.
Anyway - the trunk lid now works perfectly. It was a quick and easy fix.
Michael
Anyway - this gadget stopped working a few weeks ago. It kind of died a slow death - at first, the power open and close function became intermittent but we could still operate the trunk lid manually, and eventually, the whole thing died, which meant that the electrically operated trunk latch would not engage when the trunk lid was closed. Although the lid stayed in the closed position, the annunciator light in the instrument panel was always on, indicating that the latch was not engaged.
I dropped by my VW dealer to ask for some help, and they did a diagnostic scan of my Phaeton. This returned a fault code stored in the J605 Trunk Lid Control Module, which is a slave controller to the J393 Central Control Module for the Comfort System (you can see the Phaeton convenience system network topology at this post: Convenience System Controllers). The fault code stored was "00317 - Rear Lid Control Module (J605) 014 - Defective", which was pretty definitive. So, the Phaeton technician at my VW dealer ordered a new control module. It showed up 3 days later, and he sent me an email inviting me to drop by whenever I wanted, because it would not take very long to replace this part.
He was kind enough to allow me to take some pictures of the part and the disassembly process, here they are, in step by step format, in case anyone has a similar problem in the future.
1) Lower the big panel in the 'roof' of the trunk compartment, to allow you to get access to all the electronic controllers.
This panel is held in place by 9 Torx head screws. 7 of the screws are around the perimeter of the panel, 2 are located in the middle of the panel. The screws are all covered with a black flock finish, to match the panel, and finding the screws is a bit like looking for a black cat in a coal mine at night. You need quite a bright worklight to find them.
When you have all the screws removed, the panel will lower. It is hinged at its forward edge.
2) Remove and replace the controller module.
This is very quick and easy, it is 'plug and play'. Like most other control modules in the Phaeton, it is easiest to remove the electrical connector first, then physically remove the module. When installing the new module, put it in place first, then plug it in second.
The first hint we had that things were going well was when the trunk lights illuminated as soon as the new controller was installed. It seems that operation of the trunk lights, as well as latch operation, raising and lowering the trunk lid, and pinch protection are all controlled from the J605 module.
3) Adapt the new module, so it knows the position of the trunk lid when it is fully open and fully closed.
Most controller modules in the Phaeton need to be 'adapted' whenever a new control module is installed. Adaptation is the process of familiarizing the module with the signals coming from the components that it controls, so that it can properly operate them. It's exactly the same process as what you do when you set new tire pressures in your TPMS - what you are doing is 'adapting' the TPMS to the new pressures, so it knows what the acceptable range is.
To adapt the J605 module, open address 46 (the J393 Central Control Module for the Comfort System), select function 10, adaptation, and go to channel 22. Close the trunk lid (it won't latch, but put it in the fully closed position) and then re-enter 0 (zero) as the adaptation value. Next, move the trunk lid to the fully open position, go to channel 23, and re-enter 0 (zero) as the adaptation value. Now you have defined the extreme limits of movement of the trunk lid, and the new module will work perfectly.
It is important to note that the new module will not work at all unless you adapt it. This is not mentioned in the Phaeton service manual, because it is assumed to be common knowledge for every control module. Also, note that you cannot directly address the J605 module, because it is a slave to the J393. This is why you open the J393 controller (address 46) when you want to adapt the trunk lid control module.
Anyway - the trunk lid now works perfectly. It was a quick and easy fix.
Michael
