I just bought a 2001 Discovery SD. The vehicle has an automatic transmission. About 2 weeks after I bought the vehicle, I had to have a new battery installed. Soon after the battery was installed, my check engine light came on. I hooked up my OBDII reader to it and received the code related to Gear 4 Incorrect Ratio. Does anyone know what this means and what impending doom am I looking at if any.

Jim

 

I understand that sometimes when you fit a new battery you have to reset a few things.. but as I don't have any f this fancy electronic stuff on my landies I don't know how you would do it..

 

I believe I had the same code. I took it to the dealer and I ended up replacing the mass air flow meter on my own. It is a bosch product and easily snaps in place. As soon as it was installed and I drove my disco, service engine light extinquished. Hope this helps.

 

A low battery will cause the trannys ECU to thru that code. Go to a good tranny shop ask them to read and clear the code and you should be fine.
Mike