Basically, the P0206 OBDII diagnostic code means that the Powertrain Control Module (PCM) has detected a fault in an injector wiring harness, or the fault may be in the injector itself.
The Powertrain Control Module (PCM) often checks the injector. The PCM needs to see a voltage near 0 when the injector is on. When the injector is off, the Powertrain Control Module (PCM) expects the injector voltage to be high or close to battery voltage. Likewise, the resistance is frequently monitored by the PCM. In the event the Powertrain Control Module (PCM) does not observe the expected fuel injector voltage, or the resistance is low or excessively high, the P0206 OBD2 fault code will be set.