Address the battery issue. The low voltage code is one that self clears when the voltage is restored to normal and it passes normal diagnostics a few times. Something that occurs in the first 10 seconds or less. You can verify using jumper cables or a battery booster gizmo and turning on ignition an...

The wiki says: "Engines were fitted with either a 5-speed (M47) or 4-speed+overdrive (M46) manual gearbox or an automatic transmission, either Aisin-Warner AW70/71/72 (3-speed+overdrive) or ZF 4HP22 (4-speed) for some B230FB (or E) and diesel engines. In 1995, the manual gearbox was replaced wi...