1999 Town Car Transmission Overdrive Switch

Location

The overdrive switch is located on the center console, to the left of the gear selector. It is a small, black button with the word “Overdrive” printed on it.

Function

The overdrive switch turns the overdrive function of the transmission on or off. Overdrive is a gear that allows the engine to run at a lower RPM at highway speeds, which can improve fuel economy. However, overdrive can also make the transmission shift more frequently, which can be annoying in some situations.

Troubleshooting

If you are having problems with the overdrive switch, there are a few things you can check:

* Make sure that the switch is turned on. The switch should be in the “On” position when you want the overdrive function to be active.
* Check the wiring harness. The wiring harness for the overdrive switch is located under the center console. Make sure that the harness is properly connected and that there are no loose wires.
* Test the switch. You can test the overdrive switch by using a multimeter. Set the multimeter to the ohms setting and connect the probes to the terminals on the switch. The switch should have a resistance of 0 ohms when it is turned on and an infinite resistance when it is turned off.

Replacement

If the overdrive switch is faulty, it will need to be replaced. Replacing the overdrive switch is a relatively simple procedure that can be done in about 30 minutes.

Here are the steps on how to replace the overdrive switch:

1. Disconnect the negative battery terminal. This will prevent any electrical accidents from happening.
2. Remove the center console. The center console is held in place by a few screws. Remove the screws and carefully lift the center console up and out of the way.
3. Locate the overdrive switch. The overdrive switch is located on the left side of the gear selector. It is a small, black button with the word “Overdrive” printed on it.
4. Disconnect the electrical connector. The electrical connector for the overdrive switch is located on the back of the switch. Press the release tab on the connector and pull it straight up.
5. Remove the old overdrive switch. The old overdrive switch is held in place by a single screw. Remove the screw and pull the old switch straight out.
6. Install the new overdrive switch. Insert the new overdrive switch into the hole and tighten the screw.
7. Reconnect the electrical connector. Push the electrical connector straight down onto the new switch until it clicks into place.
8. Reinstall the center console. Carefully lift the center console up and into place. Tighten the screws that hold the center console in place.
9. Reconnect the negative battery terminal. Tighten the nut on the negative battery terminal until it is snug.

Once you have replaced the overdrive switch, test it to make sure that it is working properly.