Psm help needed on 996 update

Hi folks. Advice needed please if anyone has any insight. 996 c2 3.6 changed rack and steering shaft now psm/abs failure. Scanned with foxwell and steering angle sensor no signal. Live test shows nothing when I turn the wheel. Sits at 720 degrees and never moves. Ive cleared codes but no change. Even if it needs calibration I would have thought live data would show movement when the wheel is turned?? Any help at all would be great. I thought wheel had stayed straight but must have moved. Here is the thing I don't get. The wheel has not moved in relation to the short spline shaft in the column that the two piece shaft goes onto (from column to rack) surely the wheel is straight and the angle sensor is in the same position in relation to the wheel. The lower shaft onto rack should not affect anything as there is no sensor on the rack and steering shaft. Hope this makes sense and aware I'm rambling. Anyway any thoughts would be great. Cheers.

If live data is stuck at 720 degrees and does not move at all when you turn the wheel, that usually points to no signal from the steering angle sensor, not just a calibration issue. If it only needed calibration, you would normally still expect to see the angle change in live data, just from the wrong starting point. So I would be thinking: 1. sensor unplugged or wiring disturbed 2. sensor failed or 3. something in the column/sensor area has been upset during the work The rack or lower shaft being fitted off-centre can cause problems, but it would not usually cause the live steering angle to stay completely dead. IMHO No movement in live data = likely sensor/signal issue, not just recalibration.

In the 911uk workshop-manual thread https://911uk.com/porsche/pdf-porsche-workshop-manual-for-996-carrera.58747/ Check the chassis/steering and electrics sections, plus wiring diagrams, for steering angle sensor, PSM and ABS references.

Thanks for taking the trouble to reply. I agree, no movement on live data looks like sensor is faulty/unplugged etc. All very strange. The steering shaft I used is a Boxter 3.2 2002 shaft and looked identical to the one I removed. I can't see that being anything to do with it but thought id mentioned it. This all started with play in a front strut. My goodness what a money toilet its becoming Steering rack pipes were so corroded into rack I had to cut the pipes and use hydraulic fittings to joint the pipes with the -6 and-8 adapters into the rack. Really has been a mission. Anyway ill check out the link you sent and do some head scratching. Cheers.

That 2002 Boxster shaft can be correct for a 996 C2 3.6, but only if the actual part number or spline/joint geometry matches. “Same shape” is not the test. Part number, spline engagement, pinch-bolt groove position, collapsed length, and UJ freedom are the test. I believe the 996 part is 99634700701 or 99634702300/01/02, does that match what came off your car ? It will to your point bolts up but the spline engagement or pinch-bolt position is wrong, that is where trouble starts.

Ill check the part number of tge shaft but really can't see why it would stop the angle sensor giving a signal. There us power to the angle sensor and the scanner picks up if it's plugged in or not but nothing coming out of it. There is power to it. Ive taken it off and opened it up to have a look if there us anything obvious. Ill attach pics. One of the pads the cog sits on is quite worn. Might be this and a coincidence the sensor is not outputting. Totally get you ref splines and pinch bolt location etc. This would not stop the angle sensor working though as far as I can see as it has no bearing on it. Thanks for input mate. Much appreciated.

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Highly unlikely anyone is interested but thought id give an update so far. Used Durametric and calibrated no problem.....ish. The problem was nothing more than low voltage meant it needed calibration. Until the correct device (Durametric) was used the angle sensor could not be read. Beware of flat batteries causing this. Anyway, next problem, on live data straight ahead is zero and as you turn to the right it reads correctly. Turn to the left and the numbers are bonkers. A few degrees to the left and it reads 168990. Hmmm. The above pics show one side of the pick ups on the pc board looks fried, hence its ok one way but not the other. Ill fit a new angle sensor then calibrate and update.

You’re not rambling — this is actually a well-known issue on the Porsche 996 Carrera 2 after steering work, and your symptoms point pretty clearly in one direction. What your symptoms suggest Steering angle stuck at 720° with no change “No signal” from steering angle sensor No response in live data when turning the wheel That combination almost always means the steering angle sensor (SAS) isn’t being read at all, not just that it needs calibration. Key point to understand You’re right that: The rack itself has no sensor However: The steering angle sensor sits in the clock spring behind the steering wheel It tracks rotation internally, not at the rack So anything that disturbs the column or its alignment can affect it indirectly. Most likely causes 1. Clock spring / SAS issue (most likely) This fits your symptoms best. If the steering wheel or column rotated while disconnected, the clock spring can over-rotate and break internally Or a connector may not be fully seated Typical result: No signal No change in live data Fixed reading (like your 720°) 2. Column-to-rack alignment issue Even if the wheel appears straight: The rack may not have been centered during install The column and rack could now be out of sync This usually causes incorrect readings, not a total loss of signal — so less likely in your case. 3. Calibration needed You’re absolutely right to question this. An uncalibrated sensor will still show movement in live data Yours shows nothing So calibration alone won’t fix it. 4. Wiring issue Possible if: Something was disturbed during the work A connector or wire was strained or damaged What to check next Step 1: Inspect the column area Disconnect battery Remove airbag and steering wheel Check: Clock spring connectors Wiring condition Anything loose or misaligned Step 2: Check clock spring condition It should rotate smoothly left and right Should have equal turns each way from center If it feels Stiff Limited Clicking or binding …it may be damaged. Step 3: Re-check with scan tool Look at live steering angle data again If still no movement → confirms sensor or connection fault Step 4: Calibrate (only if signal returns) Once you see live movement: Perform steering angle calibration Wheels straight ahead Flat ground Important clarification This is the bit that causes confusion: “The lower shaft shouldn’t affect anything” Mechanically that’s true. But: The steering angle sensor works on relative position If anything rotates while disconnected, it can lose its reference or be damaged Based on your symptoms: Most likely cause: clock spring / steering angle sensor fault Calibration alone won’t fix it The rack job likely caused it indirectly (through movement or strain during installation)

Quotes source post: 2796861

AI is unfortunately rubbish for car maintenance...simply hasn't been trained on enough/high quality data to provide meaningful help

It’s a good starting point if you don’t know where to start or have tried other fixes that haven’t worked.

I think my post and pics have got lost in the telling somewhere. Anyway, best let the post die now I think.