Does receiving a cell phone call interfere with Intoxilyzer 5000 breath tests? Must a cell phone be transmitting to cause radio frequency interference to an evidentiary breath test instrument? Some experts opine that police radios and cell phones are only a problem if there is a TRANSMISSION from the breath room. This video suggests otherwise. This instrument is in need of maintenance. More research is required to determine if approved instruments are reliable when cell phones are permitted in the breath room. Range Exceeded means that the instrument was reading apparent BrAC beyond its capabilities. Invalid Sample means the instrument thought it was seeing mouth alcohol effect caused by recent consumption of alcohol. Almost any error message can erroneously be caused by RFI.