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Discussion Starter #1 (Edited)
Just bought a 07 and the roof gets to the point where it is supposed to separate from the pillars and start to store but it quits there. The side flaps are open and all sensors are in the correct position per Ross-Tech video.

A scan of the bits in measuring block 2 at that point shows:

110010001001

So it is saying the hall sensors are all in the correct position, and the pillar locks are in the released position. I can move the top slightly to confirm it is not locked down but the lifting stage of the closing procedure never starts and after brief attempt to do so the hydraulic pump stops (presumably a safety cut-off).

Anyone have any tips on how to troubleshoot it from here on out? There are no stored faults in the module and generally things seem to be clean otherwise. Former owner claims it worked fine until a few weeks ago when this happened. Any help would be appreciated!

In short, if you look at their photo #7 that is where my roof stops and the bits in measuring block 2 are all like they have them:

 

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Your next step would be to read the VW self study programme about the Eos. This will give you an understanding of how the hydraulic pump works, what components are involved and what you should expect to see.

You might want to consider investing in a VAS5054 as that has the guided fault finding that you can use to walk through each step of the roof open/close procedure manually and it tells you what to check if one part of the roof operation doesn't work. (You will likely find that the checks refer to the workshop manual, so it's worth finding a copy of that)
 

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You brought all the relevant info to the table - Thanks!
but the lifting stage of the closing procedure never starts and after brief attempt to do so the hydraulic pump stops (presumably a safety cut-off).
Diagnostics has monitored all the sensors as 'normal' but it doesn't know what the pump is doing. The roof will stop when the sequence even if normal 'times out'. That is, the next stage wasn't reached in a certain time. There's hydraulic bypass for overload in the pump (but you would hear that louder sound), thermal protection (unlikely) and a big fuse.

Lifting back the top roof segments demands a huge effort from the roof pump. Lid swing and rear window frame require far less hydraulic effort. If you get a cloned VAS5054 you can manually force the pump to operate without sensors or the controller stopping it. But there are a few things you can try without it:

Remove the spare wheel and its cover shelf, open the ski hatch so you can hear the pump better. Try to open the roof and listen at the stage when the top segments should move back. Is the pump trying to run at this stage but stops after a few seconds (Controller has timed out) or does the pump not start or starts with a normal sound then cuts off dead?

I'm wondering if your pump or its wiring or connections have a high resistance? The pump could run for the less demanding stages but not when it needs maximum power to move the top back. The easiest way to confirm this is to measure the pump current during its operation but since that could be up to 40 Amps, you won't have the means to do it. The next alternative is to clip a multimeter on the fat wires of the pump connector, extend the test leads through the ski hatch and monitor the d.c voltage on the pump. This voltage will be about 12 Volt but reverses after the first stage of roof operation. With the engine running, monitor the pump voltage when the roof op starts. When the pump is running you should see around +12Volts or -12volts. If you see the voltage drop to something less e.g 5V, you could have a pump, wiring or dirty connector problem. Watch the voltmeter very carefully when you get to the faulting stage because this is when the pump voltage should reverse if what I've read is correct. If the pump voltage cuts off immediately and the pump stops, that will be the controller stopping it because it thinks something is wrong OR the pump voltage isn't reversing.

Voltage reversal to the pump is done by the roof controller. If you are not seeing a voltage reversal, then that's what I'd suspect is the fault. Unless you are into microlectronics repair, the solution is probably a replacement roof controller. Diagnostics don't monitor the power drive to the pump, only the time out will occur because the pump doesn't have the reversed voltage to operate. This is a subtle fault scenario when most will replace the roof controller, but I hope I've explained some simple voltmeter checks to verify this.
 

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Discussion Starter #4
Thanks for the pointers. So this morning I opened up the pump housing and it is perfectly clean, no signs of an water damage and I tested the solenoids with an ohm meter and each one tested at about 9.5 ohms. I am thinking it is either the controller or the pump that is causing the problem. I ordered a clean looking used controller off ebay for $59 and can try that out easily enough. The controller is easier to replace than the pump and if it does turn out the pump is the culprit then at least I will have a spare controller that I know is still good. Wish me luck!
 

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Good luck. Testing the pump voltage with a multimeter is just as easy and faster then waiting for the replacement used controller to arrive.
 

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Discussion Starter #6
Thanks again. I'll give that a try next. I was reading the VW explanation of how the top works and it does look like the pump reverses direction after the first step of the opening process and mine completes that step. Mine gets to step 4 which is where it quits. The pump motor sounds normal to me (I owned another eos so am used to the way the process works). My gut tells me the controller isn't sending the next step of the opening operation to the pump correctly or maybe is prematurely tripping a time-out to the system. Anyway, since the controller is pretty easy to replace, and pretty cheap it's worth shotgunning it this time. I'm not in a hurry to get it back on the road...just bought it because it was a nice clean car that was being sold cheap because of the top fault.
 

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Discussion Starter #7
I learned the hard way that the trunk lock release must be controlled by the top controller because after I removed it the trunk got latched and there was no way to release it short of using the emergency release lever on the back side of the trunk lid. Oh well, live and learn!
 

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You're lucky it worked. If the lid pull down has left the lid in the locked and raised position, the emergency release wire doesn't always work. The pull down motor module only gets control signals from the roof controller. The upper lock gets a CANbus open signal from the roof controller, but it's control is in the convenience module.
 

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Discussion Starter #9
The lid wasn't pulled down, it just latched because I carelessly let it down too far after I removed the old module to get the PN off it. None of the controls (remote, door switch or lid emblem release) would release it. I couldn't find the little red ring people have mentioned but had a long umbrella that I could stick through the pass-through door and push the release handle down with and that did it. Now the lid is up and will stay up until the new module is installed. The new module is supposed to be here Thursday so I will just wait until it arrives to do any more troubleshooting.
 

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Discussion Starter #10
I did separate the controller's board from the basket shaped carrier to have a look around and could see no signs of any obvious damage. No burned components or tracings. I was surprised to see no mechanical relays on the board so the power for the motor must be switched on and off by the circuit itself which probably explains the giant heat-sink on the back. It will be interesting if replacement of the module solves my problem.
 

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I came across my thread contribution for the sunroof just by chance when I had the headlining down and had to resync the sunroof motor. In this thread I highlighted in bold that if the sunroof doesn't move right back to its extended position for a roof op.:
The roof side members DO NOT separate from the 'A' Pillars.
 

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Discussion Starter #12
Well, my saga has a happy ending. I received the used controller and installed it but no joy. Same exact issue. I learned one thing from this exercise and that was that my old controller was apparently working fine. I next put a voltmeter on the motor leads and saw the voltage dropped to 0 when the system stopped. Still no fault codes. Then I saw the post above. I followed the steps to initialize the sunroof since my symptoms were exactly like those in that thread (The sliding sunroof is initialized as follows: Start the engine and fully close the sunroof. Pull up and hold the sunroof switch for about 10 seconds until the roof moves briefly. Then release the switch. Pull the button up again within 2 seconds and hold it there until the sunroof is fully closed. It is now calibrated.). In 10 seconds my roof was fully functioning! Woo-hoo! So now I have a spare controller (my original) and a fully functioning top which cost me literally nothing but time to fix.

Now I am on to the next project - replacing the elastic strings which are frayed and one is already broken.

Does anyone know if there are instructions on how to do it (the order or any tips)? I bought the kit for $100 and it's a lot of strings. I was going to enlist my wife's help. We figured we'd start by taking a bunch of photos of what's there and try to replace them one at a time on one side so we had the other side as a guide if we screwed up. Anyone has a better idea or some actual instructions I would love to hear it.
 

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Sorry I was late with the sunroof calibration. I did say measure the pump voltage which would tell me something, but you said it was o.k and reversing?

Strings are a challenge as they seem to run through dark hard to get to places. I've had some strings off and used several colors of paint to mark their positions, but as you say each side is a mirror image of the other. You will probably have to remove the top side interior trim cappings which is an interesting challenge. Even more challenging if you have to actually remove the painted top side members. It's probably about time you stumped up for the workshop manual?

We look forward to seeing your write up contribution?
 
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