Car Speedometer Stopped Working and Transmission Not Shifting

Possible Causes

There are several possible causes for a car speedometer to stop working and the transmission not to shift. Some of the most common causes include:

• A faulty speed sensor. The speed sensor is a device that measures the speed of the car’s wheels. If the speed sensor is faulty, it can send incorrect information to the speedometer, causing it to stop working.
• A problem with the wiring. The speedometer and transmission are connected by a network of wires. If any of these wires are damaged or disconnected, it can cause the speedometer to stop working and the transmission not to shift.
• A problem with the transmission control module (TCM). The TCM is a computer that controls the transmission. If the TCM is faulty, it can cause the transmission to stop shifting.

Troubleshooting

If your car’s speedometer has stopped working and the transmission is not shifting, there are a few things you can do to troubleshoot the problem.

1. Check the speed sensor. The speed sensor is usually located on the transmission. It is a small, black device with a wire connector. To check the speed sensor, disconnect the wire connector and measure the resistance between the two terminals. The resistance should be between 100 and 500 ohms. If the resistance is not within this range, the speed sensor is faulty and needs to be replaced.
2. Check the wiring. Inspect the wiring between the speed sensor, the speedometer, and the TCM. Look for any damaged or disconnected wires. If you find any damaged wires, repair them or replace them as necessary.
3. Check the TCM. The TCM is usually located under the dashboard. It is a small, black box with a wire connector. To check the TCM, disconnect the wire connector and measure the voltage between the two terminals. The voltage should be between 12 and 14 volts. If the voltage is not within this range, the TCM is faulty and needs to be replaced.

Repair

If you have identified the cause of the problem, you can repair it yourself or take your car to a mechanic. If you are not comfortable working on your car, it is best to take it to a mechanic.

The cost of repairing a car speedometer that has stopped working and a transmission that is not shifting will vary depending on the cause of the problem. If the problem is a faulty speed sensor, the cost of the repair will be relatively low. However, if the problem is a faulty TCM, the cost of the repair will be higher.

Conclusion

If your car’s speedometer has stopped working and the transmission is not shifting, it is important to troubleshoot the problem and repair it as soon as possible. Driving a car with a faulty speedometer and transmission can be dangerous.