P2046 code definition
The P2046 code indicates that there has been a malfunction in the reductant injector air temperature sensor circuit.
What the P2046 code means
The reductant injector is part of the system that reduces the gas that is expelled through either the catalytic converter in gas engines, or the particulate filter in diesel engines. There are sensors in the exhaust system, used by the reductant injector to input voltage readings to the PCM. These readings allow the PCM to monitor the exhaust system operation, in particular the pressure and the temperature. If this code is stored, it means that the PCM detected that the temperature for the system was not correct.
What causes the P2046 code?
In most cases, this code is the result of corroded, burnt, or damaged wiring, connectors, or other electrical components. However, the PCM may detect an issue if:
- The exhaust gas temperature sensor is shorted.
- The reductant temp sensor is faulty.
- The owner has installed an aftermarket off-road system that decreases the backpressure.
- There is an exhaust leak.
What are the symptoms of the P2046 code?
The Check Engine light will be illuminated, and the vehicle may expel heavy black smoke when accelerating.
How does a mechanic diagnose the P2046 code?
In order to diagnose this code, the mechanic should first begin by inspecting the electrical components, and repairing any that are damaged, corroded, loose, or shorted. In many cases, this will solve the problem behind the P2046 code. After performing this task, the code should be cleared from the PCM, and the system should be retested.
If the code reappears, then the mechanic should continue with a visual inspection of the exhaust gas temperature sensors, as well as the related circuitry. A digital volt/ohmmeter may be necessary to compare the voltage reading with the manufacturer’s specifications. The mechanic should always clear the code and retest the system after each possible repair, to ensure that they’ve made the proper diagnosis. Once the faulty component is found, it should be repaired or replaced as necessary.
Common mistakes when diagnosing the P2046 code
Most often, mistakes are made when this code is misdiagnosed for a different code entirely. Oxygen sensors are often replaced instead of exhaust gas temperature sensors, for example, which does not solve the issue causing the P2046 code.
How serious is the P2046 code?
While this code won’t directly affect the drivability of the vehicle, it is still considered an important issue that should be dealt with immediately. Without the ability to properly monitor and control the exhaust system, the vehicle will not pass an emissions test. Ignoring this issue could result in larger and more expensive repairs in the future.
What repairs can fix the P2046 code?
In order to repair the cause behind the P2046 code, the mechanic may:
- Replace faulty electrical components.
- Replace a shorted exhaust gas temperature sensor.
- Replace a faulty reductant temp sensor.
- Repair an exhaust leak.
Need help with a P2046 code?
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