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Any idea where i can order to make a part?

Yeah, being Hall effect and 3 wire, they likely send a return voltage when they're "active." If one of them never sends a return signal there may be an issue with it. The idea to try running the pump directly is probably a good one. At the same time you might want to do a pressure test at the output.
I forgot those were hall switches, they probably need power to test them, the continuity test I suggested would only work on a "real" switch. Lots of info on how to test hall switches on line. If you swing that sensor with the two switches in it do you feel a little pendulum swinging in it? What activates the hall switches?
Giving 12 volts to the valve is a good idea but didnt you already do that with no change to pump output?
Thinking some more on that sensor, maybe there is no pendulum inside it and it uses the hood linkage to know what the angle is. So if it is not mounted where it can sense the linkage then it wont work right. This would be a better design to not have a little swinging part inside the switches ALWAYS swing around as you drive wearing itself out. Just thinking out loud, so something else to double check....if this is the case the switches could still be good??
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I regret not taking a picture when I took the sensor apart.
It's very small, like 1 inch by 1 inch or so.
Inside of it, there's a little metal tablet. It moves along a channel.
I'm gonna find a picture online and post it.
There's no switches per say.
I have no idea how this sensor translates the angle information it receives.
I tried looking up hall sensors, it talks about magnetic fields.
But here's the sensor. Picture worth a thousand words !:)


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As far as testing the valve, no I have not tried it yet, because I don't know what voltage it needs to operate at. Maybe it needs 1 volt, and I don't want to burn it by giving it 12 volts 😀
Cool, so the little round tablet is steel and the hall switches sense it.
I saw this earlier on testing hall switches, I dont know this stuff very well anymore but it looked OK. It shows having the switch wired in and "working" and take readings with the multimeter probes plugged into the wire terminals. Maybe you need a short wire like a section of paperclip to get into the connector if you test leads are to big.
To recap, connect the multimeter’s black probe to a ground connection, the hall sensor’s black terminal, and the red probe to its supply terminal directly or via a jumper wire.

Check the reading on the multimeter. It should be around 12-13 volts. The reading shown in the example below is 11.73 volts, which can be considered acceptable.

Yes that's pretty much exactly the test I did and described in post #45.
Only my readings were about 0.5 volts, nothing like 5 or 12v.

What sucks is that I don't know the proper values for this sensor. Neither for testing voltage or resistance.

Im going to try to find someone with the same system and ask them to measure the voltage at the valve connector, to see what voltage I need to supply. Then go from there.
Is there power coming out of the box that the wires to the trunk sensor switches connect to? I think it was wire 1 and 2? I think you checked thatin post #60 and had almost nothing out of the control box?
Are you talking about the rear lid control module?

Pins 9 and 14 go directly to pins 1 and 2 on the tilt switch sensor.

Basically I already measured voltage on pins 1 and 2 so it would be the same.

If I understood your question correctly.
Are you talking about the rear lid control module?

Pins 9 and 14 go directly to pins 1 and 2 on the tilt switch sensor.

Basically I already measured voltage on pins 1 and 2 so it would be the same.

If I understood your question correctly.
Yes, 9&14 or 1&2 are each end of the same wires. (from schematic segment post #58)
So you got nothing out of pins 9 or 14?
I'll double check again, I don't remember anymore:)
Too many tests.

I had some test their system for me, and they're getting 12 volt on the valve connector. By disconnecting that connector, their trunk acts just like mine.

Also, interestingly, I found someone having the exact same problem, and apparently wiring was at fault. He didn't post how he found then problem or what he did to fix it, but he stopped posting after he thought it was K wire was improperly connected. I thought he must've fixed it, and that's why never posted back.

I asked my friend and confirmed he is getting 12v at the connector by the valve.
So I shorted both connectors for the pump with a wire, that way the valve connector also gets 12 volts.
I saw a NOTICEBLE improvement.
The trunk would close on its on and it would pull hard.
Unfortunately it's still not strong enough to open from the bottom position, but opens from about 3/4 closed.
So definitely a difference, but not enough.
So I suspect the pump is too weak, and the hydraulic trunk module is faulty, not sending a signal to the valve.
I guess at this point I can ask the seller to send another pump and module, and maybe the position sensor, and see if it fixes the problem.
I don't know what other tests I can try at this point.
Alright everything makes sense now.

He must've send me the wrong module and wiring.

Wiring was pre wired for 2 pins on the tilt sensor.
It's because it was for sure from E39 touring, which uses only 2 wires.
I couldn't figure out forever why it had only 2 wires, being oem wiring harness, and colors were different from the diagram, and I had to add another wire.
This also explains why there's no continuity for grounding the tilt sensor.
Even though I added a 3rd wire, the module is programmed for E39 touring, which only has 2 wires.

Now no power to the valve connector makes sense as well.

On E39 touring, vs E38, the pump only has 1 connector. On E38, there's two connectors, one for the pump, one separate for the valve.

Since the module is programmed for E39 Touring, it is not outputting voltage to the pump valve, as that connector didn't exist on E39 touring.

So everything makes sense now, the module is coded for E39 Touring, while the pump and tilt sensor I have are for E38.

I tried disconnecting the tilt sensor yesterday, with power connected to the valve.
I observed that if I pressed the trunk open/close button, the trunk would start closing and would stop right away. Probably in the absence of the tilt sensor input, the module stopped lowering the trunk.

On the second press of the button, however, the pump would run full cycle, when opening the trunk.
That's probably because the module is coded for a tilt sensor with only 2 pins. So even though the tilt sensor was disconnected, the pump did not stop working to open the trunk.

And the last problem, of course, is the pump seems to be clearly too weak/worn out to open the trunk.

I'm glad I opened a case with ebay right away and did not take chances.
The seller sent me a new pump and module, so I hope they will work.

I looked up the seller on Google maps and the reputation is less than stellar. I wonder if he knew the pump was defective in advance...

Lots of people buy these retrofits and don't install them for years, as it's a major undertaking, so by that time all return policy is long gone...
Yes I owe you guys so much for helping me with this retrofit, definitely taking me x100 times longer than I anticipated.
Still weird that I can't even scan the module with diagnostic software, it's not showing up.
Yet it kinds works, so weird that I can't scan it.
Got another module and another pump. The module now sends the proper voltage to the valve, but still the trunk won't open.
Still weird that I can't scan the new module either.
Maybe I can hire someone to take apart the pump and repair it...