P118B Code - Particulate Matter Sensor Temperature Not Plausible
Quick Answer
The particulate matter (PM) sensor monitors the amount of the particulates (soot) in the diesel exhaust gas exiting the tailpipe. Common causes include Faulty Exhaust Particulate Matter Sensor, Exhaust Particulate Matter Sensor harness is open or shorted, Exhaust Particulate Matter Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P118B indicates Particulate Matter Sensor Temperature Not Plausible.
- Common causes
- Common causes include Faulty Exhaust Particulate Matter Sensor, Exhaust Particulate Matter Sensor harness is open or shorted, Exhaust Particulate Matter Sensor circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P118B Description
The operation of the PM Sensor is based on the electrical conductivity characteristic of the diesel particulate. As the exhaust gas flows over the sensing element, soot is absorbed in the combs between the electrodes, eventually creating a conductive path. When the path is formed, it generates a current based on the voltage being applied to the element. The measurement process continues until a preset current value is reached. To avoid misleading readings, the sensor performs a regeneration where the soot is cleaned off by heating up the element, before the measurement phase begins. The amount of regenerations is based on vehicle strategy; when the calibrated number of regenerations is reached, the cumulative current readings are used to determine the amount of soot concentration in the exhaust gas which in turn determines the collection efficiency of the diesel particulate filter (DPF).
What are the Possible Causes of the DTC P118B?
- Faulty Exhaust Particulate Matter Sensor
- Exhaust Particulate Matter Sensor harness is open or shorted
- Exhaust Particulate Matter Sensor circuit poor electrical connection
How to Fix the DTC P118B?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P118B code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P118B Audi — Bank 4 Probe 2 Voltage Too Low Leakage Air
- P118B Buick — Particulate Matter Sensor Temperature Not Plausible
- P118B Cadillac — Particulate Matter Sensor Temperature Not Plausible
- P118B Chevrolet — Particulate Matter Sensor Temperature Not Plausible
- P118B GMC — Particulate Matter Sensor Temperature Not Plausible
- P118B Volkswagen — Bank 4 Probe 2 Voltage Too Low Leakage Air
Frequently Asked Questions about P118B Code
1. What are the common symptoms of OBDII code P118B?
- Common symptoms include poor engine performance, decreased fuel efficiency, and the illumination of the check engine light.
2. What can cause the OBDII code P118B to trigger?
- The code P118B is typically triggered when the particulate matter sensor temperature reading is not plausible, indicating a possible issue with the sensor itself or the related components.
3. How serious is the OBDII code P118B?
- While the code may not cause immediate harm to the vehicle, it should be addressed promptly to prevent potential damage to the emissions system and to maintain optimal engine performance.
4. What are some possible repair tips for fixing the OBDII code P118B?
- Repair tips may include checking the wiring and connections to the particulate matter sensor, inspecting the sensor for damage or contamination, and verifying the sensor's temperature readings.
5. Can I continue driving with the OBDII code P118B present?
- It is not recommended to drive with the code P118B active, as it may lead to increased emissions, reduced fuel efficiency, and potential long-term damage to the vehicle's engine and emissions system.
6. Is it possible to reset the OBDII code P118B without addressing the underlying issue?
- While clearing the code may temporarily turn off the check engine light, the underlying issue causing the code will persist unless properly diagnosed and repaired.
7. How can I diagnose the OBDII code P118B?
- Diagnosis typically involves using a diagnostic scanner to retrieve the code, conducting visual inspections of the sensor and related components, and performing tests to verify sensor functionality.
8. Are there any recalls related to the OBDII code P118B?
- It's advisable to check with the vehicle manufacturer or authorized dealerships for any recalls or technical service bulletins related to the particulate matter sensor temperature issue.
9. Can a DIY enthusiast repair the OBDII code P118B?
- Depending on the individual's skill level and access to tools, some DIY enthusiasts may be able to address the OBDII code P118B by following repair guides or consulting with automotive forums for assistance.
10. How much does it cost to fix the OBDII code P118B at a repair shop?
- The cost of repairing the OBDII code P118B can vary depending on the specific cause of the issue, but it may involve sensor replacement, wiring repairs, or other related repairs, potentially ranging from $100 to $500 or more.
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