COM2003 Removal & Teardown - Steering Column Controls Unit

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haydent
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Joined: 22 Jul 2014, 10:55

COM2003 Removal & Teardown - Steering Column Controls Unit

Post by haydent »

Just want to share my experience inadvertently pulling apart the 'clock spring' ribbon cable and geared mechanism and supporting pcb that handles the steering wheel angle sensor, steering wheel column switches and airbag/horn wiring connection rotation.... Now im not 100% this is the way to put it all back together, but it works for me, so if you have take yours apart, make sure to take note of the way its put together.

Serial Number 96611304XT

COM2003 Remove & Refit , Citroen C5 Steering Column Switch Module


COM2003 Teardown - Steering Column Switch Module


* After re-assembly make sure it can rotate atleast 2-3 turns each way from the center indicator to make sure you wont damage the ribbon.

Rear of PCB, Showing all the pads the switch sticks work on, also at the top, is the socket for the Key RF receiver.
DSC_9664.JPG
Front of PCB, showing hall effect magnetic sensors circled in white that determine the current wheel rotation number
Circled in Red is the wheel angle sensors, looks like IR, with transmitter and receiver on opposite sides of the 2 tracks for the toothed rings to pass by, blocking or not in various patterns.
DSC_9666.JPG
The 'toothed ring rotator', and the way i set it up before putting it back together, so in the wheel up right position, the magnet on the small cog, is over the middle magnetic sensor from the previous image. And the notch that rotates it on the big tooth ring, opposite it, so its half way between that position. (The clock spring can do 6 turns, 3 each way, but only 2 each way are displayed on the window letter codes when assembled (see last image), and then of that the wheel itself on my car can only do 1.5 turns each way.
DSC_9669.JPG
Opposite side of toothed ring, inside clock spring, enter with care. The top circled, narrowest spline fits in the clock spring front plate such that is at the top of the steering wheel. Also note the circled lower right arrow used to indicate the orientation window, see video. There is a small cog that sits in the geared race, and drives the white clock spring reel.
DSC_9670.JPG
My Model
IMG_20170110_123432.jpg
From what i can tell the Key Fob RF Reciever.
IMG_20170110_125336.jpg
The manual's notes on the alignment inspection window.
Capture.JPG
Last edited by elma on 12 Jan 2017, 07:15, edited 10 times in total.
Reason: utube link

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Stickyfinger
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by Stickyfinger »

I take it this is an old unit used to find out how it works.
Good to see the details, please upload to the new server storage so these images do not disappear from a 3rd party host.

haydent
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by haydent »

The images are attached using forum feature.
This is the live unit ! The reason i took it apart, is that we where getting intermittent errors relating to the angle sensor.

Im also looking into a used replacement com2003
Last edited by haydent on 11 Jan 2017, 11:06, edited 1 time in total.

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Stickyfinger
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by Stickyfinger »

It is all Harry Potter to me...

I like hitting things with hammers :)

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Dommo
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by Dommo »

Hello

Have you managed to get the unit to calibrate? I either have the error:

"Temporary fault - no communication with the steering wheel angle sensor incorrect value received"

Or something along the lines of it needing recalibrating and needing the error reset. But I find it near impossible to calibrate using our Lexia. We've tried driving along at a slow speed in a straight line and pressing calibrate, but it doesn't seem to work or if it does we're not doing it correctly.

Is it normal to find that the straight ahead position is around 30 something degrees, then it flicks to 100 and something degrees? I had a quick look online and this appears to be either a common problem, or normal function.

Thanks

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Paul-R
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by Paul-R »

Dommo wrote: But I find it near impossible to calibrate using our Lexia. We've tried driving along at a slow speed in a straight line and pressing calibrate, but it doesn't seem to work or if it does we're not doing it correctly.
When I reset the C5 I simply reversed for a bit and then drove forwards in a straight line. That ensures that the wheel is in the straight ahead position.

With the car now stationary I then did the calibration. Absolutely no need to have the car in motion and even it will calibrate I reckon that you'll be making micro-adjustments which would throw the calibration off.
Dommo wrote: Is it normal to find that the straight ahead position is around 30 something degrees, then it flicks to 100 and something degrees? I had a quick look online and this appears to be either a common problem, or normal function.
I do seem to remember something along those lines as well but can't swear to it.

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Dommo
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by Dommo »

Ah, well, I did try it stationary but we had found online that someone said to drive slowly while doing it. So we have tried to do it while not moving (after getting things straight), with no luck!

Thanks for replying.

haydent
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Re: COM2003 Teardown - Steering Column Controls Unit

Post by haydent »

Hi, i just did it on the spot, engine off, ignition on. the first time i put my com2003 back together i didnt have the mag sensor cog in the right way and it would not callibrate. But this time around it callibrates.

In mine it tells me to turn the ignition off/on, rotate 1/4 turn left and right, make sure wheel is straight and then continue. (the on/off it does not really check for, but it will fail if you dont do the 1/4 turn each way. as for being perfectly straight it should not stop it completing (as long as you are not off too much). All that not being straight will do is affect the effectiveness of the callibrated result. Also after calibrating do an error clear, as even old errors about not being calibrated, once it is calibrated will stop the angle reading from updating.

But i do still have the problem you are talking about and there is a you tube video in french showing it and a few discussion threads too that i have not read all off. Im not sure if its normal behaviour or not.

In the ABS parameter reading, it shows wildly large angle (365568.4 deg at center, going up and down by 100000 deg per turn) that does change with the wheel , and the esp and headlights work with and dont complain about. In the notes page for this reading (F6) it does say min/max is -610 to 610 deg .... which makes me think there might be a problem...

But the suspension ecu has been throwing an error only visible in lexia P05D2 "Permanent fault No communication with the steering wheel angle sensor incorrect value received" , and if i go into parameter measurement here it shows about -128deg as center and goes up down jumps neg and positive all over the place. In the notes page for that reading it does say however that the reading is not used in the current height correction version, which makes me think it might not have been coded to be compatible...

The way this suspension ecu angle readout is very familiar with how ive seen computer code behave when a number outside the expected range for a data type is cast as that data type, as what might happen when the ABS ecu sends it to the Suspension ECU, the susp ecu will expect a number of a certain size, like Int8 or Int16 but is getting one bigger than this and treating it the same, and thus garbling the data.

Im going to keep trying to find out if this is 'normal' behaviour or not, and possible source a cheap replacement unit.

Images to come

haydent
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Joined: 22 Jul 2014, 10:55

Re: COM2003 Teardown - Steering Column Controls Unit

Post by haydent »

I found this comment: (translated from polish) http://klubcytrynki.pl/forum/index.php?topic=97322.0
These two errors virtual. This plus the display of a diagnostic error, any error in fact there is only Lexia afford it "creates", which was even in one of the Info'Diagów. The second error of the steering angle too, because it appears in all known C5 me, including my own. Lexia test the steering angle shows the wrong values ​​(the setting wheel perfectly straight shows tens of degrees, after a slight movement to the left the value of the red, etc.), but if one uses instead Lexii Peugeot Planet (equivalent Lexii for Peugeots) are the same test shows the correct value (zero in front etc.). The conclusion is that this Lexia has a bug. This may be due to the fact that these versions ECU suspension does not benefit from the steering angle (this is even written in the help file in Lexii) because there is no communication between the sensor and the ECU suspension, which Lexia mistakenly treated as an error at the time of diagnosis suspension .

Both errors must p**s. They do not exist normally, they are produced only at the time of making the diagnosis Lexie. You can leave or delete each - to choose from.

haydent
Posts: 56
Joined: 22 Jul 2014, 10:55

Re: COM2003 Removal &Teardown - Steering Column Controls Unit

Post by haydent »

added video and new pics to opening post