How to replace Steering Wheel Position Sensor (SWPS).
This is a pretty common part to fail on the 2000+ Bonnevilles. When it fails, it gives you the “Service Stability System” message on the DIC. The only way to know for sure that the SWPS is the culprit is to verify with a Tech2 scanner (or compatible).
This is not an easy fix, but not extremely difficult. It took me about an hour, but I have taken these cars apart a few times.
1. Remove driver side kick panel, held on with two 9/32” screws.
2. Disconnect electrical connectors from the light and temp sensor.
3. Remove lower column panel by pulling straight back.
4. Remove knee bolster by removing four 10mm bolts.
5. Remove these two 10mm bolts to remove the connector bracket.
6. If there isn’t a cut in the boot, make a 3-4” slit to be able to access the bolt. Using a 13mm socket, remove the nut from the column. You will have to turn the wheel to get the nut on the bottom side.
7. Once the nut is removed, turn the wheel 180° and remove the bolt.
8. The column is held up with four 13mm nuts. When removing these, be careful as the column will want to drop. A second person might be handy to hold the column up while you remove the bolts, but not necessary.
9. Once column is no longer secured, remove it from the car. Make sure you have disconnected all the wiring before yanking it out.
10. Remove the boot to expose the SWPS.
11. Remove the blue retaining clip.
12. Release white clips (if any) that hold the SWPS down, and simply lift up on it. It might give a bit of a struggle at the end of the shalf, but just keep pulling.
13. The column has to be eyeballed straight. The indents on the shalf take care of the rest. If installing a new SWPS, it will come preinstalled with an alignment pin. Do not remove this until the sensor is installed. If installing a used SWPS (as I did), you will need to center the sensor yourself. The FSM does a poor job of explaining how to do this, but you need to make the little dot (circled in yellow), line up with the hole (circled in red) as you push the sensor down into place.
14. After the sensor is seated, put the blue retaining clip back in place.
15. And then reinstall the boot.
16. Complete the procedure by installing everything back in the order you removed it. You will find that hooking up the column to the steering half is easier if you don’t have the column secured. The most frustrating part for me was getting the column connected to the steering shaft. Have patience, and a friend holding the column helps. Once you get everything back together, take it for a drive. You shouldn’t have any “Service Stability System” messages anymore. Using the Tech2, I was able to see that the SWPS was working correctly, and it was showing the steering angle was 0° going straight down the road at 60mph.
