For 1990-2009 cars

Problem | Action
--- | ---
Low fluid | Add fluid.
TV cable out of adjustment, binding or damaged | Adjust or replace the throttle valve cable.
Shift select cable out of adjustment, biding or damaged | Adjust or replace the shift select cable.
Manual valve binding or sticking | Inspect the valve body.
Throttle valve binding or sticking | Inspect the valve body.
B2 control valve binding or sticking | Inspect the valve body.
Accumulator(s) pistons damaged or leaking | Inspect the accumulator pistons.
Accumulator(s) seals cut or damaged | Inspect the accumulator seals.
Accumulator(s) broken or distorted springs | Inspect the accumulator springs.
Incorrect line pressure | Perform the line pressure diagnosis.