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P118BModerateEmissions

P118B on 2015-2019 Opel Zafira (Zafira Tourer C) — Particulate Matter (PM) Sensor Temperature Not Plausible

1 vehicles · 1 makes · $200-$600 repair

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Most Reported On

2015-2019Opel ZafiraZafira Tourer C

P118B is an OBD-II diagnostic trouble code meaning “Particulate Matter (PM) Sensor Temperature Not Plausible.” P118B is a GM manufacturer-specific code (Chevrolet, GMC, Cadillac diesels) indicating the engine control module detected an implausible temperature reading from the exhaust Particulate Matter (PM/soot) sensor located downstream of the diesel particulate filter (DPF). The PM sensor uses an internal heater and temperature element to monitor soot accumulating between its electrodes; when the reported temperature does not match expected exhaust conditions, the ECM cannot trust the sensor's soot measurement and sets this code, often illuminating the check engine light and disabling proper DPF/emissions monitoring. This code is most commonly reported on 2015-2019 Opel Zafira (Zafira Tourer C), with repair costs ranging from $200 to $600.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (2)
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Common Causes

1Faulty or aged exhaust particulate matter (PM) sensor
2Open, shorted, or chafed wiring in the PM sensor harness
3Poor electrical connection or corrosion at the PM sensor connector
4Exhaust leak near the PM sensor altering measured temperature
5Failed PM sensor internal heater or temperature element
6ECM/sensor control unit software or calibration fault (less common)

Typical Repair Cost

$200 - $600

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

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Best Value$90–$120

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Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

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Professional$350–$450

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Vehicles Affected (1)

Opel P118B page →
ZafiraModerate

NOx Sensor / SCR System Failure on Euro 6 Diesels (Zafira Tourer C)

2015-2019$200-$6000 reports

Related Codes (8)

01447EVAP System (VAG)P0401Exhaust Gas Recirculation Flow InsufficientP0402Exhaust Gas Recirculation Flow ExcessiveP0403Exhaust Gas Recirculation Circuit MalfunctionP0404Exhaust Gas Recirculation Circuit Range/PerformanceP0410Secondary Air Injection System MalfunctionP0411Secondary Air Injection System Incorrect Flow DetectedP0412Secondary Air Injection System Switching Valve A Circuit

FAQ

What does P118B mean?

P118B stands for "Particulate Matter (PM) Sensor Temperature Not Plausible." P118B is a GM manufacturer-specific code (Chevrolet, GMC, Cadillac diesels) indicating the engine control module detected an implausible temperature reading from the exhaust Particulate Matter (PM/soot) sensor located downstream of the diesel particulate filter (DPF). The PM sensor uses an internal heater and temperature element to monitor soot accumulating between its electrodes; when the reported temperature does not match expected exhaust conditions, the ECM cannot trust the sensor's soot measurement and sets this code, often illuminating the check engine light and disabling proper DPF/emissions monitoring.

What are the most common causes of P118B?

The most common causes of P118B are: Faulty or aged exhaust particulate matter (PM) sensor, Open, shorted, or chafed wiring in the PM sensor harness, Poor electrical connection or corrosion at the PM sensor connector, Exhaust leak near the PM sensor altering measured temperature, Failed PM sensor internal heater or temperature element, ECM/sensor control unit software or calibration fault (less common). The specific cause varies by vehicle.

How much does it cost to fix P118B?

Repair costs for P118B range from $200 to $600, depending on the vehicle and root cause.

Which vehicles are affected by P118B?

Au7o has documented P118B across 1 vehicle models from 1 manufacturers: Opel.

Sources (2)

  • articleNOX Sensor Fehler am Opel Zafira C Tourer nach 80000km — MOTOR-TALK
  • articleNOx Sensor — Opel Zafira Tourer C 2.0 CDTi B20DTH (Motordoctor)

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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