I'm from Norway, and it is 35 years since I left school, so please let me know if my writing is hard to understand. It sure is hard for me to find the correct words! :-)
My 2000 XKR that I imported from California last year, had the more or less standard faulty steering wheel tilt function.
That means that in Auto it would retract the steering wheel to the most upper position, but when I put the key back in it would not tilt down. Using the tilt button or the memory button just made it click, click, click.
I search the forum for a solution, and found some more or less misleading information, and thought I could clear up some of the misunderstanding on how this actually works.

One suggestion is cutting the white/blue wire to the position sensor of the tilt motor, another is to cut the wire and solder in a resistor. (2.7 Kohm is suggested) Don't do that!
- Why not? It works!
Well, if you just adjust your tilt and reach manually, its fine. But if you use the Auto function, your steering column will hit your wooden dash panel and push it pretty hard.

Another misunderstanding is that the tilt motor it self has a mechanical stop. No it has not!
- But I disconnected the tilt rod, pushed the tilt-button / memory button / removed the key, and is stopped after a while!
Yes but that's because one of three reasons:
1. Your position sensor works and stopped the motor (as it should)
2. Your position sensor hit its mechanical stop, and the motor stopped because the current draw got to high. (and you where lucky not to break the position sensor)
3. You removed the position sensor, and the motor stopped because of a built in timer.

The tilt motor has a position sensor connected to the output shaft of the motor through a little "gearbox". The position sensor is just a standard potensiometer, and will give a voltage feedback to the BCM.
When you use the Auto function, the BCM give voltage to the tilt motor, and shut off when the feedback from the position sensor hits 3.4 Volts. That is the electrical stop function.
If you cut the white/blue wire (or solder in a resistor), you remove (or lower) the voltage feed to the potensiometer, and the BCM will never see the 3.4 V feedback. The tilt motor will just continue until you hit the mechanical stop in the steering column, and either stop because the current went to high, or just wait for the timer and then shut off power to the motor.

I hope you understood my explanation, and got a better understanding of how this works.
I will write a little how-to later in this thread on how you can test, trying to fix and properly adjust the position sensor relative to the tilt movement of the column.

 

OK. So what to do?
This is my suggestion with some more explanation.
- Move the steering wheel all the way out
- Remove the dashboard under cover (two screws at the bottom, two clips at the top, and two electric connectors)
- Remove the two screws holding the tilt motor (4mm hex)

Tilt motor screw location

- Move the motor assembly forward to disconnect it from the tilt rod.
- Loosen the white cable connector from the steering column by pushing it upwards and disconnect the connector itself.
Now reach under the steering column cover and try to rotate the tilt rod by hand. This should move quite easily. If not you can try lubricate the tilt pivot point etc.

Look at the tilt motor assembly, cut the zip tie (if fitted) and unhook the position sensor and lift it off the motor.

Zip tie and Phillips screw


Square rod


- Try to rotate the square rod sticking out of the sensor with your fingers. You should be able to turn this approx. 3.5 turns in total - end to end.
- If not, remove the small Phillips screw (see above photo), gently pry out the two securing tabs, and lift off the lid from the sensor.
- Push on the end of the rod and remove the rod (with gear) underneath you should see a spring washer. Flatten it out with your fingers, grease the rod, washer and gear and put it back together.
- Hopefully you should now be able to turn the square rod by hand.

Connect an ohm meter between the white/blue and pink wire coming out of your position sensor
Twist the square rod slowly from fully left to fully right (3.5 turn) while you keep an eye on your ohm meter. It should measure from (approx.) 220 to 2270 ohm, without any weak spot, blackouts or irregularity.
- If not try to clean the potensiometer inside the position sensor with some electronic cleaner and test again. If this fails, you will not be able to fix your Auto tilt and reach.
Now slowly turn the rod until you read 530 ohm at the meter.
- Reattach the position sensor to the motor assembly. You may have to adjust the rod slightly to match up with the square hole in the motor shaft.
- Secure tit with a new zip tie.

Back to the car;
- Move the steering wheel all the way in (forward) with the tilt / reach switch
- Twist the tilt rod by hand until the top cover of the steering column nearly touch the wooden dash panel.
- Move the steering wheel all the way out again
- Reattach the motor assembly, while (if necessary) twisting the tilt rod anti clockwise (moving steering wheel down) to allign the tilt rod.
- Connect the white connector.
Test tilt and reach manually with the switch, set it to Auto and remove the key from the ignition while you watch the upper cover vs wooden panel.
- If it hits the dashboard, loosen the motor again and twist the tilt rod half a turn anti clockwise.
- If it stops with a too big gap, twist the tilt rod half a turn clockwise.
Test again!
(If you are like me and are not satisfied with the gap, you can find a middle setting by take out the position sensor again, and move the square rod 1/4 turn)

Hope this helps!

 

Some numbers:
Bare in mind that my measurements are only from my car with my multi meter. How big if any differences there may be through the lifespan of this electrical tilt and reach system from Bosch I do not know.
The voltage to the position sensor (white/blue wire) is 4.2 Volts, I have seen in several threads that this is called the 5V feed
On my car the tilt function always stop when the voltage between the pink wire and ground is between 3.4 and 3.5 Volts.
If I disconnect the white connector with the tilt fully up, the resistance between the white/blue and pink wire is 530 Ohms.

If your potensiometer in the position sensor has some erratic readings in the low end of the resistor, that be when the steering wheel is at the highest. You can try to connect a resistor in parallel with the potensiometer and with a little luck move the point of electric stop away from the worn part of the potensiometer. You can do that by soldering a resistor between the white/blue and pink connector. I have tested this with a 2.7 Kohm resistor who gave me a additional 0.15V at the same position of the position sensor. So may be a resistor between 1 and 3 Kohm could be considered.

Good luck, and please give me some feedback from your measurements if you test this on your car.

 

Thanks for your efforts. I know this has been a recurring problem over the years for some owners....