Diagnosing a Siemens EM232 module problem

[rbduck1]

I'm new here. I'll make this, hopefully, as clear and concise as possible. I am using a s7-200 siemens plc cpu type 224xp with the em232 analog output module. I'm having a problem getting any output from any of three EM232 modules. These have no dip switches. When connected, they all have 24 volts input for power. When connected to 24v, none have the green 24v LED lit. I have tried several 24 volt supplies. Also, in the V4.0 Step 7 Microwin programming software, under the PLC>Information tab, all three modules indicate
"no user power/module error"

The problem may be as simple as having three bad modules. That's what I'm trying to clarify.

I hope this enough information. Does anyone have an insight?

 

[rbduck1]

I did find my problem and I want to thank all that responded to my question. It should have been obvious, but with the way things have been lately, the obvious was not as simple as it seemed. The problem was the analog card bad.