Code Definition

P1152 — HO2S Bank 2 Sensor 1 Signal Above 0.45v (A/F Ratio Too Rich)

System: Powertrain  |  Type: Manufacturer-Specific  |  Make: Mazda

About P1152

P1152 is a manufacturer-specific powertrain diagnostic trouble code recorded for Mazda vehicles. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P1152 is stored, the module has detected a bank-specific fault, meaning it applies only to one cylinder bank of a multi-bank engine; and a sensor-related fault — the reported value from the named sensor is out of spec.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

P1152 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.

Code Information

The upstream heated oxygen sensor (HO2S) on Bank 2 Sensor 1 reports exhaust oxygen for Bank 2 to the Powertrain Control Module (PCM) as a switching voltage, high for rich and low for lean. DTC P1152 sets when this sensor signal stays above about 0.45V and does not switch, telling the PCM the air fuel ratio on Bank 2 is too rich or the sensor is biased high. This can be a genuine rich condition from excess fuel or restricted air affecting Bank 2, or a sensor or wiring fault. On V engines Bank 2 is the bank that does not contain cylinder number one. The driver may notice a fuel smell, black smok...

Join TaT to view the complete code information and diagnostic details.

Quick Facts