C70: Hall sensor error

[davec916]

Hi. I have a C70 2007 D5. When using the luggage lift a Roof Service message would appear on the dash and the lift would not work.

I've seen this problem in forums before but there is an added twist to my problem!

I was getting a Hall Sensor 3 error message on my icarsoft scanner which I managed to fix (wire was broken where the leads from the sensor enter the main loom) I can now see active and passive states on the scanner and record 10V and 13V across the terminals of the sensor.

However another fault code has appeared on Hall 13. I get Active/Error states showing in the iCarSoft data for that sensor as I open and close the boot with the roof down.

I know these two sensors are used with the luggage lift facility.

Does anyone have any idea why Hall 13 would go into error after fixing Hall 3 ?

Any advice appreciated!

[Baxlin]

Hi, Dave, I’m sorry that I can’t help with your question, but could you post a couple of pics of where the actual cable break was, please?

On mine, pressing the yellow button disables the roof, but I ‘recovered’ it by multiple pressing of the roof close button. Reading on here, it seems a cable break is at least as likely as a sensor failure, hence my request.

Thanks, and apologies again for hi-jack.

Malcolm

[davec916]

Originally Posted by Baxlin

Hi, Dave, I’m sorry that I can’t help with your question, but could you post a couple of pics of where the actual cable break was, please?

On mine, pressing the yellow button disables the roof, but I ‘recovered’ it by multiple pressing of the roof close button. Reading on here, it seems a cable break is at least as likely as a sensor failure, hence my request.

Thanks, and apologies again for hi-jack.

Malcolm

Hi Malcom,

The two wires from the Hall 3 sensor connect into a thicker part of the trunk loom. It's there that the wires break and cause errors when the Yellow Lad Assistance button is pressed. A friend of mine has exactly the same break at the same point on his T5.

I removed the rear seat and backrest as well as the side panel where speaker is installed. Then you'll see Hall 3 sitting on top of the metalwork. The cable goes down into the wing cavity and joins the loom. I had one wire broken there my friends cable was completely severed. I had to take the cloth loom tape off to see the break (see pic). I managed to fix it by taking out the tweeter and soldering the wires back together. Hall 3 was now fixed.

Things have moved on! I got an error for Hall 13 once 3 was fixed. I found 13 and checked the magnet that operates it. All was OK. I then noticed on the diagnostics that Hall 13 was either Active or in Error. With the roof down I jiggled the loom from Hall 13 and got a 'permanent' Active. In this condition the Load Assistance functioned! That loom where Hall 13 goes to is I believe the same loom that Hall 3 is attached to. Clearly there is an intermittent wiring fault in that loom. I suspect it's where the loom bends with the boot opening and closing.

I intend to fix the Hall 13 intermittent fault but there was another thing not quite right. When the Load Assist raises the roof in the boot it appears to be out of adjustment. The panels tend to come out at a slight tilt towards the back of the car and the lowest panel is not raising much so you don't get the amount of access you should to the lower space.

It might need a re calibration.

Any ideas welcome!

[Baxlin]

Phew!!

Thanks so much for going into such detail, Dave, much appreciated.

No wonder I couldn’t see anything amiss by just looking at the hinge area....

[davec916]

Originally Posted by Baxlin

Phew!!

Thanks so much for going into such detail, Dave, much appreciated.

No wonder I couldn’t see anything amiss by just looking at the hinge area....

The loom runs along the hinge on the inside. It forms into a loop in the cavity where the mid range speaker is situated. A bugger to see let alone work on!

I intend to rebuild the loom from Hall Sensor 13 back to the connector situated on the plastic panel below the speaker. I'll try and use a more flexible cable. Should sort the sensor problem out.

Good luck!