HO2S Bank 1 Sensor 1 Heater Circuit High Input
P1136 — HO2S Bank 1 Sensor 1 Heater Circuit High Input
System: Powertrain | Type: Manufacturer-Specific | Make: Mazda
P1136 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 P1136 is stored, the module has detected a signal or supply voltage higher than the expected operating range; 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.
P1136 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.
The Powertrain Control Module (PCM) controls and monitors the heater element inside the Bank 1 Sensor 1 upstream oxygen sensor to bring it to operating temperature for closed loop fuel control. DTC P1136 sets when the PCM detects a high voltage, or high input, on the HO2S heater monitor circuit, which typically indicates an open circuit, an open heater element, or loss of current flow so the monitored voltage stays pulled high. On Mazda systems this most often points to an open in the heater wiring, a poor connection, or a burned out heater element rather than a sensor signal problem. The driv...
Detailed possible causes for P1136 are available to TaT members.
Unlock with Free TrialStep-by-step diagnostic guidance for P1136 is available to TaT members. Our Diagnostic Assistant provides professional-level troubleshooting procedures written by experienced technicians.
Unlock with Free Trial| Code | P1136 |
| System | Powertrain |
| Type | Manufacturer-Specific |
| Make | Mazda |
| Causes | Available |
| Diag. Assistant | Available |
| Video | — |
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