What does P0730 mean on a Chrysler 300?

P0730 on a Chrysler 300 (and most other vehicles) means Incorrect Gear Ratio. This is a general transmission code, and it doesn't specify *which* gear is having the problem. The PCM (Powertrain Control Module) has detected a mismatch between the expected gear ratio and the actual gear ratio being used by the transmission.

This code requires further diagnosis to pinpoint the exact cause. Possible culprits include:

* Transmission problems: Internal transmission damage (worn gears, clutch packs, etc.), low transmission fluid, or a faulty valve body are all common possibilities.

* Speed sensor issues: Problems with the vehicle speed sensor (VSS) or the output speed sensor (OSS) can lead to incorrect gear ratio calculations.

* Other sensor problems: Faulty sensors related to transmission operation can also cause this code.

* Wiring issues: Damaged or shorted wiring related to the transmission control system.

You should not attempt to drive the vehicle extensively with this code. Continuing to drive with a transmission problem can cause further and potentially more expensive damage. It's crucial to have a qualified mechanic diagnose the underlying issue using a scan tool to get more specific information and perform the necessary repairs.