Since the automakers are becoming more responsible towards environment sustainability and trying to lessen their carbon footprints in compliance to meet current emission legislation standards, various types of soot sensors also known as particulate matter sensors have been developed for all modern diesel vehicles to estimate the amount of soot in a diesel particulate filter and remain law compliant. These sensors fitted at upstream of the exhaust system detect excessive PM emissions downstream of a DPF in case of a filter failure.

P24c600 particulate matter sensor is used to control and diagnose emission system utilizing DPF and mainly developed to perform two functions:

  1. To accurately utilize DPF regeneration strategies, estimating soot amount in DPF.
  2. To trigger an OBD fault signal by detecting DPF failure resulting in excess PM emissions.

These sensors are developed and provided by trusted and reliable developers including Bosch, Delphi, Continental, Sensata, EngineSens, and others.

How Particulate matter sensor works?

Soot-particle-sensing element consists of two inter-digital comb-like electrodes (IDE) with an initially infinite electrical resistance, an internal heater and a positive temperature coefficient resistor for temperature measurement and PM sensor function is based on resistance measurements and during this sensor operation, soot particles are collected onto these inter-digital electrodes leading to a drop of electrical resistance based on the applied voltage to the element.

Soot particles are deposited and form conductive soot trails between the electrodes and when the sensor reaches a certain conductivity threshold, it notifies the engine system that the filters need to do regeneration process and burn particulates. The sensor element is regularly regenerated by heating prior each measurement phase and diagnostic software then uses the measured current to evaluate functional capability of DPF at a point of time. Soot particles trapped in DPF are disposed off during the regeneration process, when the particulates are burnt off.

PM sensors usually work together with NOx sensor which measures the NOx content and take care of the emissions coming out the vehicle’s engine. Ideally the regeneration process in a properly functioned vehicle occurs approximately about every 500 miles but again, it is highly dependent on the vehicle and driving conditions.

Why Particulate matter sensor fails?

P24C600 Particulate Matter Sensor Temperature Circuit Fault Code Explained

When the exhaust gasses flowing into DPF form particulate matter that is too large to be trapped within the DPF and regeneration stops, it gives rise to excessive soot accumulation which clogs the diesel particulate filter causing PM sensor to fail. In such instance, an instant cleaning of DPF is advisable otherwise it might trigger error codes related to PM sensor. You could notice it through bad readings, faulty EGS-PM sensor unit, damaged or flooded sensor, short circuit and some other noticeable changes.

We recommend that you should not ignore these signals and immediately fix these errors otherwise you will end up paying thousands of dollars to fix or replace the damaged Diesel particulate filter (DPF).

How the damage to DPF can be avoided?

To avoid damage to the filer and enable regeneration, filter should be cleaned and refilled with adblue (DEF) fluid. In diesel fuelled cars, NOx sensor and PM sensor is critical to the Adblue SCR system to ensure your vehicle is compliant with the laws that’s why adblue technology comes as a standard in all newer vehicle models.

A common error message you receive on your instrument cluster is “Check Engine” light which notifies that the DPF needs to be regenerated.  P24C6 P24C600 Particulate Matter Sensor Temperature Circuit is the error code specific to PM sensor temperature or regeneration issue.

How to fix PM sensor temperature circuit fault code?

In initial cases, cleaning should help avoiding and fixing this error but if cleaning fails to resolve this error then the probe must be checked. Sometimes, it’s just eh probe that has failed and caused this error. In that case, replacing the probe is the only solution.

PM sensor consists of both a probe and module and cannot be replaced separately therefore they must be replaced as a unit. It could be quite technical to search and buy the right replacement part so you can contact xenons4u for the advice on correct replacement part for your vehicle.

Replacing probe follows the step by step procedure:

  • Remove the PM sensor out of your vehicle safely by getting under the vehicle
  • Gain a safe access to the sensor by pulling back the protective cover rubber and get it grabbed with an electrical tape.
  • Split the cables and connect the new probe cables with corresponding colors and solder each wire together to give them an additional strength.

This replacement procedure of PM sensor is applicable to almost all vehicle brands including Audi VW Skoda seat Mercedes-Benzes BMW Volvo daf Siemens Vdo continental Renault opal gm Vauxhall Citroen Peugeot and many others. Once the replacement is done, diagnostic run should be performed to check if the error is resolved. After the new PM sensor installation, clear the codes from instrument cluster to ensure car has adopted the new sensors.

Again, replacing the probe might be a quick task and dealing with this error on your own sound easy but it is not really an easy and inexpensive procedure so taking your vehicle to the xenons4u will help in proper diagnosis, right purchase and proper fixation of the error saving you extra dollars.