LM34: Sharing DC source

I have a 4-20mA sensor and LM34AH sensor.  The 4-20mA sensor works correctly when 24VDC source is applied.  Also the LM34AH works correctly when DC source is applied.  The issue is when both of these units are hooked up using the same power source the 4-20mA sensor is stuck a 0.46mA but the LM34AH is working fine.  If I remove the ground source to the LM34AH and put an voltmeter across the ground and output of the LM34AH the 4-20mA sensor works again.