Not true. There is no core charge with the 99 S80 module. There is no gel sealing the PCB. I opened my module (dremel tool) and inspected the soldering with a magnifying lense and found the solder bridge on the QFP, Quad Flat Pack , (Square shaped component) in the center of the board. I believe the contacts on the connector outside the module are also important for reliability and should be cleaned and coated (contact cleaner) to prevent the intermittent problem. It is worth a try to avoid the $800 price tag for a new module. Try the connector contacts if your used replacement is also causing the message. There is no reason they sealed this unit that I can see except maybe to make it difficult to get into the module. There is no moisture seal or conformal coating. Unless you submerge your car in a lake to this level, how is it a problem. I resealed mine around the border with tape and it has lasted 3 months without the error message.

I'd be curious to know what the repair involves by the individual that does this as a sideline business. What is he finding as a repairable problem? Unless you have the test capability to find defects and to functionally test the module, it is a stab in the dark to find problems.

GR