Gear shifter is in park but cluster reads sport mode car will not start

If the cluster on your 2007 Buick Lucerne CX 3.8 is showing "Drive" while the shifter says "Park" and the car won't start, there could be a few potential issues. Here are some troubleshooting steps you can try:

1. Check the shifter cable: The shifter cable connects the shifter to the transmission. If it is disconnected or broken, it can cause the shifter to not function properly. Check the cable and replace it if necessary.
2. Check the shift linkage: The shift linkage connects the shifter to the transmission. If it is disconnected or broken, it can cause the shifter to not function properly. Check the linkage and replace it if necessary.
3. Check the transmission range sensor: The transmission range sensor is responsible for detecting the position of the shifter and telling the engine control module (ECM) which gear the car is in. If it is malfunctioning, it can cause the car to not start or display incorrect gear information. Check the sensor and replace it if necessary.
4. Check the battery: A weak or dead battery can cause the car to not start or display incorrect information. Check the battery and replace it if necessary.
5. Contact a mechanic: If none of the above solutions work, it may be necessary to contact a mechanic for further assistance. They may be able to provide additional troubleshooting steps or arrange for a repair of your car if necessary.

Note: Before attempting any maintenance or repair work on your car, be sure to follow all safety precautions and refer to the owner's manual for guidance. Additionally, if you are not experienced with working on cars, it may be best to seek professional help.

Will not turn over at all ?

If you have an electronic shifter, that's the problem. These can be read for codes.

Shift cable not installed properly. There is a safety which keeps the car from being started unless its in park. There should be a xable going from the shifter to the instrument cluster. Did you connect this?

You have to locate where the park ignition switch is located. Some are on the transmission and some are in the column under the dash. It probably got moved.

Your shift lock actuator is not working. This system works off of the brake light circuits. The FIRST thing to check is your brake lamps. If they are not working, that is the reason for your shifter not working. Fix the brake lamps and your shifter will shift. (Possible defective brake lamp switch).

If your brake lamps are working, then the shift lock solenoid or its circuits are defective. In this case, you can work around the problem until you can get it fixed. Turn the ignition switch one click.(Far enough to unlock the steering wheel, but not far enough to make the lights on the instrument cluster illuminate.) The shifter will then shift out of PARK. Place the shifter in NEUTRAL and start the engine. You can then shift to the desired gear to get where you need to go. If you place the shifter back in PARK, you will have to shut the ignition off and repeat the process.

This generation of Buick seems to have a faulty speedo cluster illumination circuit.
I have an '01 and an '02 and they both have the same problem with the dash illumination.
I use the 'FEEL' sollution ;
When you start the car you can assume it is in PARK.
the next spot down with the shifter is REVERSE.

Next is going to be NEUTRAL.

And then DRIVE.

So, from PARK , 3 possitions down on the shifter is going to give you DRIVE.

The alternative is to replace the instriment cluster on you car.

there is a small cable/string attached to the steering column part of the shifter. when you move the shifter it pulls the cable/string, which moves the lever in the cluster on the PRNDL display. basically look carefully at where the shifter base is and you should find the cable/string thing, and reattach it.

sounds like brake shift interlock solenoid is bad. try doing this emergency bypass. Turn key to off position, no lights on cluster. step on brake, pull shifter out of park to neutral. start car & drive away without putting it in park. see owner manul for better description.

it is your neutral safety switch, no car since the dawn of time will start if it thinks it might be in gear. try putting it in neutral instead of park as a short term fix, but you should get the neutral safety switch replaced, it takes about 45 min for your dealership to do. the car being a 2008, the dealer will probably do this under your new car warranty.