The P21B4 fault code in automobiles indicates a problem with the exhaust temperature sensors, unintended fueling, or a damaged NOx absorber catalyst. The most common symptom is the engine light turning on. To fix the issue, one must visually inspect the wiring harness and connectors for any damage or corrosion.

The repair time for this issue is estimated to be around 1.0. It is important to address this issue promptly to avoid further damage to the vehicle.

To interpret the fault code, one must check the possible causes listed above.

Repair Importance Level10.0 (Out of 10)
Estimated Repair TimeApproximately 1.0 hour
Repair Difficulty Level10.0 (Out of 10)

If you notice the Engine Light ON or Service Engine Soon Warning Light, it could be a sign of p21b4 fault code. Here are the symptoms to look out for:

  • The P21B4 fault code in an automobile can cause several symptoms, including the engine light turning on or the service engine soon warning light appearing.
  • Other symptoms may include reduced engine power, decreased fuel efficiency, and difficulty starting the engine.
  • Additionally, the vehicle may experience rough idling or stalling, and there may be a noticeable decrease in acceleration.
  • It is important to address these symptoms promptly to prevent further damage to the vehicle and ensure safe driving conditions.

There are several causes of the automobile fault code p21b4, including failed exhaust temperature sensors, unintended fueling, and damaged NOx absorber catalyst.

  • The automobile fault code P21B4 can be caused by several factors.
  • These include the failure of the Exhaust Temperature Sensors, which can result in an in-range low reading.
  • Unintended fueling can also trigger this fault code.
  • Additionally, a damaged NOx absorber catalyst can cause P21B4 to appear on the vehicle’s diagnostic system.
  • It is important to address these issues promptly to prevent further damage to the vehicle and ensure its optimal performance.

To fix the p21b4 automobile fault code, check the possible causes and inspect related wiring harness and connectors for damage.

  • To fix the automobile fault code P21B4, first, check the possible causes listed above.
  • Then, visually inspect the related wiring harness and connectors.
  • Look for damaged components and check for broken, bent, pushed out, or corroded connector’s pins.
  • This fix will take an estimated repair time of 1.0 hour.

The automobile fault code P21B4 indicates a problem with the engine coolant pump control circuit. The estimated repair time for this issue is 1.0 hour.

The cost of fixing this issue can vary depending on the auto repair shop, but it is common for most shops to charge between $75 and $150 per hour. Other factors that may influence the cost include the severity of the issue, the type of vehicle, and the location of the repair shop.

The P21B4 fault code is related to the engine running in DeNOx mode. The Powertrain Control Module (PCM) monitors the post-injection fuel and O2 Sensor 11 values.

If the O2 Sensor 11 value remains high for a calibrated time, the fail counter is incremented by 1. If the counter value exceeds a calibrated value, the fault is set and the Diagnostic Trouble Code (DTC) will be triggered.

The P21B4 fault code indicates that the NOx absorber has exceeded a calibrated high temperature threshold for a calibrated period of time.

What are the possible causes of the P21B4 automobile fault code?

If you see the engine light on or the service engine soon warning light, it could be due to the P21B4 fault code. This code is caused by exhaust temperature sensors failing in-range low, unintended fueling, or a damaged NOx absorber catalyst. To fix this issue, you should check the possible causes listed above, visually inspect the related wiring harness and connectors, and look for any damaged components or broken, bent, pushed out, or corroded connector’s pins.

How can I visually inspect the related wiring harness and connectors to fix the P21B4 fault code?

If you’re experiencing the P21B4 fault code, which is indicated by the Engine Light ON or Service Engine Soon Warning Light, you can fix it by visually inspecting the related wiring harness and connectors. This fault code is caused by Exhaust Temperature Sensors failed in-range low, unintended fueling, or damaged NOx absorber catalyst. To fix it, check the possible causes listed above and inspect the wiring harness and connectors for any damage or corrosion. Look for broken, bent, pushed out, or corroded connector’s pins.

What are the consequences of ignoring the P21B4 fault code and not fixing it in a timely manner?

Ignoring the P21B4 fault code, which indicates Exhaust Temperature Sensors failure, can lead to unintended fueling and damage to the NOx absorber catalyst. This can trigger the Engine Light or Service Engine Soon Warning Light. It is important to fix the issue in a timely manner by visually inspecting the wiring harness and connectors, checking for damaged components, and looking for broken, bent, pushed out, or corroded connector’s pins.

p21b4 error fault code explained

If your engine light is on and the fault code is p21b4, it could be due to failed exhaust temperature sensors, unintended fueling, or a damaged NOx absorber catalyst. To fix it, visually inspect the wiring harness and connectors for any damage or corrosion, and check for broken or bent pins.

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