Having completed the diagnostic process you can make a list of items to be fixed.

If you found one or more leaking lines, you will need to feed new hard plastic line to replace it. The most common spot for cracks is at points where the lines flex often, such as in the rubber tubes that carry the lines from the body to the door.

If you found that you have a bad check valve you will simply replace it with a new one.

If you discovered one or more leaking door lock actuators you'll want to find out what style you have. The old style, with four rubber diaphragms, are very easily repaired. See this early style W123 door lock actuator repair guide.

If you found a leaking trunk lock actuator, it will likely need to be replaced. See this guide on how to replace it. If the fuel door lock actuator is leaking, and it's the early style, see this guide on how to pull it from the car and try to stop the leak. If it's the later style it will likely need to be replaced.

If you found a leak door lock master switch in your driver's door you can try fixing it by reading the repair guide before you purchase a replacement part.

Once you've fixed everything, you can return to under the hood and test the entire system by plugging your vacuum gauge in to the end of the "Y" connector that enters the lock system check valve. This tests the vacuum tank, all the lines, and all the actuators. It takes lots of pumping but it sure is rewarding to see the vacuum gauge rock solid!

Note - on this car, which had a neglected door lock system, there was a leaky master vacuum switch, a leaky passenger door lock actuator due to cracked upper diaphragms, a leaky trunk lock actuator due to a torn outer diaphragm, and finally a gas door lock leak.