P0135 is a diagnostic trouble code (DTC) related to the oxygen sensor. The oxygen sensor measures the amount of oxygen in the exhaust gases and sends this information to the engine control module (ECM). The ECM uses this information to adjust the air/fuel ratio, critical to the engine’s proper operation.
When the P0135 code is triggered, the ECM detects a malfunction in the oxygen sensor’s heating circuit. The heating circuit is responsible for quickly bringing the oxygen sensor to the operating temperature to provide accurate readings.
The causes of a P0135 code vary widely, but some of the most common include a faulty oxygen sensor, a damaged wiring harness, a blown fuse, or a malfunctioning ECM. Sometimes, the problem may be as simple as a loose or corroded connection somewhere in the system.
If you have a P0135 code, it’s essential to have the problem diagnosed and repaired as soon as possible. A malfunctioning oxygen sensor can cause various issues, including reduced fuel economy, poor performance, and increased emissions.
Repairing a P0135 code involves replacing the faulty oxygen sensor or repairing the damaged wiring harness. However, it’s essential to have a qualified technician diagnose the problem to ensure that the correct repair is performed.
The P0135 fault code indicates a heating circuit problem with the oxygen sensor. If you have this code, diagnosing and repairing the issue promptly is essential to avoid potentially serious engine problems.
Fault code P0135 indicates an Oxygen sensor heater circuit malfunction (block one sensor 1).
There are some heating components inside the oxygen sensor. This code is generated if the heater circuit is shorted or the resistance is too high. In this case, fuel consumption increases, the engine’s operation is affected, and its performance decreases.
The engine fault lamp will illuminate when the oxygen sensor heater circuit fails.
The ECU tests the oxygen sensor heater circuit each time the engine is started. In the test;
- Is there an open circuit? Is too much current drawn? Is there a short circuit? Is controlled. If one of them is detected, the P0135 fault code is generated.
The ECU also monitors the time for the oxygen sensor to warm up. If the warm-up time is longer than it should be, it will generate a P0135 error code.
P0135 Fault Code Solution:
- If the oxygen sensor heater circuit is broken, it is replaced.
- The fuse may have blown. It is replaced.
- There may be breakage, loosening, or corrosion in the wiring of the oxygen sensor heater circuit.
- Rarely, the problem can also be in the ECU.
The heater circuit fault code in the 1st block 1st sensor is P0135. If the same fault is in the 2nd block 1st sensor heater circuit, the P0155 fault code is generated.