P2196 Ford -Have 2005 Mustang GT, code came on after taking car to get dyno tuned.

Question

P2196 appears on one tune, P0053 appears on another tune.

Answer 1

P2196 Lack of H02S Bank 1 Sensor 1 switch, Sensor indicates rich

P0053 H02S heater resitance Bank 1 Sensor 1

Both code condition are for the H02S sensor of Bank 1 Sensor 1 which is the upstream 02 sensor  this just reinforce the condition that you may just have a failed H02S sensor.