I am posting this to share information from several conversations this month with owner-operators of GP38-2 locomotives, it may eventually become applicable to preservation activities since some of these units are now finding their way into museums.

Be aware that there is a significant error in most (if not all) copies of the 4th edition EMD GP38-2 Locomotive Service Manual. In the late 1970s the Dash-2 module suite used on this type of locomotive was changed with the SB and PF modules being replaced by an FP module that combines the functions of the two earlier components. The 4th edition manual reflects this change in the equipment description in the electrical chapters, but the troubleshooting section (Chapter 11) has incorrect information applicable to the earlier SB and PF combination rather than the FP module.

I am just documenting this here because of the considerable confusion and questions it causes. You need a later edition manual to get the FP module troubleshooting information. Or contact the EMD Service Department to see if they can provide a correctly printed Chapter 11.

PC