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The transmission dipstick and fill tube on left hand drive models is located back by the brake booster. The dipstick is labeled "Trans Fluid". Check the color of the fluid and if it is at the proper fill level then you will not be able to add more fluid. If the fluid is black, it will need to be incrementally drained. We have discussions on how to do this.
Adding more fluid above the marked level will cause the transmission to not shift properly. Don't add any fluid to "top off". Use the specified Toyota Type IV only and replace exactly what is drained off.