Possible causes – Faulty fuel level sensor– Fuel level sensor harness is open or shorted– Fuel level sensor circuit poor electrical connection Tech notes Low fuel level can trigger this code. Before replacing any parts try filling up the fuel

Possible causes – Faulty fuel level sensor– Fuel level sensor harness is open or shorted– Fuel level sensor circuit poor electrical connection When is the code detected? An excessively high voltage is sent from the sensor is sent to Engine

Possible causes – Faulty fuel level sensor– Fuel level sensor harness is open or shorted– Fuel level sensor circuit poor electrical connection When is the code detected? The output signal of the fuel level sensor does not change within the

Possible causes – Faulty Fuel Pump Relay– Fuel Pump Relay harness is open or shorted– Fuel Pump Relay circuit poor electrical connection– Faulty Powertrain Control Module (PCM) When is the code detected? The P0230 code will be set when the

Possible causes – Faulty Fuel Tank Pressure Sensor– Fuel Tank Pressure Sensor harness is open or shorted– Fuel Tank Pressure Sensor circuit poor electrical connection Tech notes On most Cadillac vehicles the sensor is on top of the fuel tank.

Possible causes – Faulty Fuel Tank Pressure Sensor– Fuel Tank Pressure Sensor harness is open or shorted– Fuel Tank Pressure Sensor circuit poor electrical connection Tech notes On most Cadillac vehicles the sensor is on top of the fuel tank.

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit fuse– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit open shorted to ground– Heated Oxygen Sensor (H2OS)

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit fuse– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit open shorted to ground– Heated Oxygen Sensor (H2OS) Bank

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 harness is open shorted to ground– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit poor electrical connection– Heated Oxygen

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 harness is open shorted to ground– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit poor electrical connection– Heated Oxygen

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit fuse– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit open shorted to ground– Heated Oxygen Sensor (H2OS) Bank

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 fuse– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 harness is open or shorted– Heated Oxygen Sensor (H2OS) Bank 1

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 fuse– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 harness is open or shorted– Heated Oxygen Sensor (H2OS) Bank 1

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 fuse– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 harness is open or shorted– Heated Oxygen Sensor (H2OS) Bank 1

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1– Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 circuit fuse– Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 harness is open shorted to ground– Heated Oxygen Sensor (H2OS)

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1– Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 harness is open shorted– Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 circuit poor electrical connection– Heated Oxygen Sensor (H2OS)

Possible causes – Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1– Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 harness is open shorted– Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1 circuit poor electrical connection– Heated Oxygen Sensor (H2OS)

Possible causes – Faulty Heated Oxygen Sensor Bank 1 Sensor 1– Heated Oxygen Sensor Bank 1 Sensor 1 harness is open or shorted– Heated Oxygen Sensor Bank 1 Sensor 1 circuit poor electrical connection Symptoms – Engine Light ON (or

Possible causes – Faulty Heated Oxygen Sensor Bank 1 Sensor 2– Heated Oxygen Sensor Bank 1 Sensor 2 harness is open or shorted– Heated Oxygen Sensor Bank 1 Sensor 2 circuit poor electrical connection Symptoms – Engine Light ON (or

Possible causes – Faulty Heated Oxygen Sensor Bank 1 Sensor 3– Heated Oxygen Sensor Bank 1 Sensor 3 harness is open or shorted– Heated Oxygen Sensor Bank 1 Sensor 3 circuit poor electrical connection Tech notes Replacing the O2 Sensor