This might work depending on the amount of the drip. With the engine running, pull one handle to the lock. You will know which hose it is connected to because the hose will get stiff. As you do this, watch the drip to see if it gets worse. Then push the handle the other direction to the lock. Again watch the hoses to see which one gets stiff and to see if the drip gets worse. Go through all the levers doing this. Hopefully you will find out which one is leaking.