DTC P24D0

Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5509057 Diagnostic Instructions Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions DTC Descriptor DTC P24D0 Particulate Matter Sensor Supply Voltage Circuit Low Circuit/System Description For an overview of the component/system, refer to: Exhaust Aftertreatment System Description

Component	Description
B136 Exhaust Particulate Matter Sensor	The sensor measures the particulate matter in the form of soot in the exhaust. The actual sensor surface is only a few square millimeters in size. On the surface there are 2 microscopic comb-shaped electrodes with intertwined tines (electrical traces) to have the longest possible route of transitions from one to the other electrode. Soot is conductive, therefore when soot deposits between the electrodes, electrical current can flow from one electrode to the other. The more soot deposits between the electrodes, the lower the resistance. To measure the resistance, voltage is applied to the electrodes. The voltage also generates an electrical field that attracts the soot. If the sensor surface is saturated, the sensor is electrically heated to burn off the soot. The sensor sends measured values and state of health information via serial data to the ECM and the reductant control module.
K20 Engine Control Module	The control module contains a microprocessor used to process input data to control outputs. The control module controls a series of actuators to ensure optimal engine performance. The control module does this by reading values from a variety of sensors, interprets the data and adjusts the engine actuators accordingly.

Component

Description

B136 Exhaust Particulate Matter Sensor

The sensor measures the particulate matter in the form of soot in the exhaust. The actual sensor surface is only a few square millimeters in size. On the surface there are 2 microscopic comb-shaped electrodes with intertwined tines (electrical traces) to have the longest possible route of transitions from one to the other electrode. Soot is conductive, therefore when soot deposits between the electrodes, electrical current can flow from one electrode to the other. The more soot deposits between the electrodes, the lower the resistance. To measure the resistance, voltage is applied to the electrodes. The voltage also generates an electrical field that attracts the soot. If the sensor surface is saturated, the sensor is electrically heated to burn off the soot. The sensor sends measured values and state of health information via serial data to the ECM and the reductant control module.

K20 Engine Control Module

The control module contains a microprocessor used to process input data to control outputs. The control module controls a series of actuators to ensure optimal engine performance. The control module does this by reading values from a variety of sensors, interprets the data and adjusts the engine actuators accordingly.

Conditions for Running the DTC DTC P16D7, P16D8, P16D9, U02A3 = Not set Ignition = On Ignition and Start Switch Signal = Greater than 11 V Reductant Control Module Relay = On Frequency the DTC runs = Continuously — After the running conditions are met Conditions for Setting the DTC Particulate Matter Sensor Supply Voltage = Less than 9 V Actions Taken When the DTC Sets DTCs listed in the DTC Descriptor category = Type B DTC Conditions for Clearing the DTC DTCs listed in the DTC Descriptor category = Type B DTC Reference Information Schematic Reference Engine Controls Schematics Connector End View Reference Master Electrical Component List Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs DTC Type Reference Powertrain Diagnostic Trouble Code (DTC) Type Definitions Scan Tool Reference Control Module References Circuit/System Verification

Verify DTC P16D7, P16D8, P16D9, U02A3 is not set. ⇒ If any of the DTCs are set Refer to: Diagnostic Trouble Code (DTC) List - Vehicle ⇓ If none of the DTCs are set
Verify DTC P24D0 is not set. ⇒ If the DTC sets Refer to: Circuit/System Testing ⇓ If the DTC is not set
All OK. Circuit/System Testing
Ignition/Vehicle » Off
Disconnect the electrical connector: B136 Exhaust Particulate Matter Sensor
Ignition » On / Vehicle » In Service Mode
Test for battery voltage between the test points: Ignition circuit terminal 4 @ & Ground ⇒ If less than battery voltage 4.1. Ignition/Vehicle » Off 4.2. Test for less than 2 Ω between the test points: Ignition circuit terminal 4 @ Component harness & Output terminal @ Fuse ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇓ If less than 2 Ω 4.3. Test for infinite resistance between the test points: Ignition circuit terminal 4 & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇒ If infinite resistance » Verify the fuse is OK and there is voltage at the fuse. ⇓ If battery voltage
Test or replace the component: B136 Exhaust Particulate Matter Sensor Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Exhaust Particulate Matter Sensor Replacement