Possible to show a diagram of your capacitor install on the 12v leads?My R3 on a 2016 Chevrolet SS (Holden) had the power cut out issue. Went to eBay, purchased a couple 16V 100 ufd (microfarad) 5 x 7mm aluminum electrolytic capacitors, wired them to the 12V leads, PROBLEM SOLVED. No issues since. The capacitors were $1.00 plus $2.99 shipping plus tax. I have one left over for another vehicle, if needed.
Easy and no need to run any more wires.
Note: This issue was not evident with a BEL 300 detector; apparently, the R3 is sensitive to transients on the line.