my 98 ls 400 keep display tail lamp failure and low washer fluid warning, i went to auto zone and replace all the bulbs in the back and still have same problem, any ideas why? and the low washer fluid warner, have no clue what to do

 

you might try doing a search or checking the high mount lights....

on the washer, (assuming you have filled it up) try unplugging it and plugging it back up, or get ready for a possible switch replacement. also do a search to see what others have done.

good luck..

 

The bulbs in the center brake lamp drift over time. So if one isn't burnt out it may still trip the computer. The solution is to replace the bulbs in the center brake light, even though they don't need it.

 

you did have someone stand on the brakes while you looked at the lights right?
most often yeah it's the high mount light.

The most obvious solution for the washer fluid is to FILL UP THE WINDSHIELD WASHER FLUID
if that doesnt work, then yeah, I would (and have) just disconnect the sensor plug (don't unscrew the sensor!!) from the bottom of the reservoir. you could attempt a float repair but it'll just die over time again.

 

i agree with what everyone said above, if none of that works then you might have to replace the sensors like the brake light switch and the washer level sensor.