I contacted John, the maker of the Safeguard (buy it, its amazing) and he thinks that this is happening due to the signal output not being strong enough to drive the analog input on the ms. Here is the technical information he provided to me....
The driver chip is LM3914. Pin 9 is left open, which selects dot mode. I doubt it's actually switching to bar mode, probably something else going on.
The output that drives the gauge is from a resistor, so it may not be strong enough to drive the analog input on the EMS. Make sure the EMS input is set for high impedance. Disable pull up or pull down resistors on the input.
I have attached a portion of the schematic that shows the output circuit for the gauge. It's a home made 4 bit R1-2-4-8 D/A resistor ladder. Software limits the max count to 10, and R39 loads the output so the max signal is 1.3v to match the bargraph input. R40 and Z4 are to protect the uP from bad things. J1-2 goes to the "ring" terminal of the gauge.
R35=80K
R36=40K
R37=20K
R38=10K
R39=3.65K
R40=1K
Z4=5.1vz
Any ideas on how I can verify that my input is running in hi-z mode or doesn't have any pull up/down resistors? Id love to be able to data log this AND have the gauge working correctly!