1999 chevy won't come out of 4 low, tried shifting to neutral, actuator is good, no codes come up on scan.

Your problem shows as a problem with a 1999 Chevrolet C1500. Then you describe the problem as not coming out of 4-wheel Low. If your Truch HAS 4 wheel drive, it is a "K" series truck, not a "C" series truck. K1500? (Minor detail, but some people don't know the difference and can give you some really goofy advise if they try to look it up the way it is listed.)

Anyway, I have to ask this: Did you actually scan your transfer case module or did you scan with a generic OBD code reader? It should be noted here that MOST OBD code readers CANNOT access information from the transfer case or body control modules. They can only access the "GENERIC" side of the engine control computer (or PCM). They also cannot access "vehicle specific" information from ANY modules including the PCM.

With this type of problem, you really need a full access scanner that can read data from all of the modules. That is the only way to check and see if the computer is getting the signals from the control switches to change your drive mode. If the computer is not receiving the signals, then there is a problem with your selector switch or the wiring between the switch and the computer. If the computer IS getting the signal, then there is a problem either with your shift actuator motor assembly or the wiring between the computer and the shift actuator.

Reading the data will also verify the range that the actuator is reporting to the computer. Just because the motor runs, does not mean the actuator is functioning properly. It COULD be reporting to the computer that it is in 2-wheel High when it is actually stuck in 4-wheel Low. This is where comparing computer data to functional testing comes in.