The lens extends and retracts constantly after turning it on. Battery has a good charge.

Try the following steps when the lens is stuck and will not open, retract, or extend.

1. Turn the power off, eject the battery pack, and reinsert it into the camera.
2. Turn the power back on and check if the drive part of the lens moves properly.
3. If the lens still will not open, retract or extend, then reset the camera.

I only can think of two reasons. The first, the battery does not have enough power. As a safety precaution it shuts itself down, to avoid damage to the saved pictures. Because if the voltage is to low, it can't write with 100% accuracy.
Second: something is blocking free movement of the lens. This could have a cause inside the lens barrel, and you won't see a thing. It also could be a minute damage on the outside of the lens. Or what sometimes happens while putting the camera on, you touch the lens barrel. I assume you did remove any lens cap attached to the camera.
So if you can't see any damage to the lens barrel, charge the battery and try again.

Typical lens error. You will need a replacement lens.

If this camera has a rechargeable battery in it You Will Have to Get a new battery for it(Your Description indicates a Bad Battery Cell). If it uses AA Rechargeable Batteries they will Need to Be Replaced.

Lens error is usually caused by mechanical faults concerning lens assembly. The lens cannot extend or retract fully, the error is detected and lens error is returned.
Sometimes this can be fixed playing with the lens during extraction or retraction to help the lens asset getting back to normal.
More often the camera lens must be disassembled and re-assembled by a technician to fix the problem.

This is due to a fault in the circuitry inside the camera that controls the retraction/extension motor. Unfortunately, this needs to be fixed in a camera workshop.
/Chris

If the lens is stuck out extended you may want to call Olympus Customer Service to discuss repair process and pricing. If the battery is fully charged and the lens still stays extended then this is a clear repair issue as something in the lens assembly has failed. Their telephone number is 800-622-6372 option 2 and then option 3

Belikes, any external object is trapped in between your Lens Motor and Camera Body. You should consult Authorized Service Personnel to handle this trouble.

The only thing not functioning was the lens I could turn on off see menus etc but could not take a picture and the lens would not retract - My husband cleaned the battery terminals on battery & in camera -IT WORKED !!!! good as new -

When the battery dies, usually the camera will retract the lens if possible. If the battery is so dead the lens can not retract, I would recommend trying to charge or change the battery. Or try to turn the camera on, and then manually shutting it off if you can.