What does engine code P0736 reverse incorrect ratio means?

Engine code P0736 indicates a problem with the transmission, specifically that the transmission is experiencing an incorrect gear ratio in reverse. This can result from issues such as low Transmission Fluid, a faulty transmission control module, or mechanical problems within the transmission itself. When the vehicle attempts to engage reverse, the system detects that the actual gear ratio does not match the expected value, triggering this diagnostic trouble code. Addressing this issue typically requires a thorough inspection of the transmission and its components.