Code 15 & 23: Left/Right Heated Oxygen Sensor - Inactive

WARNING: This page is about a different car, the 1995 Mazda 929. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Trouble Code No. 15/23 Left/Right Heated Oxygen Sensor - Inactive

Fig 2: Trouble Code No. 15/23 Heated Oxygen Sensor Circuit Diagram