DTC P200C - LNP or LNQ
Diagnostic Instructions
DTC Descriptor
DTC P200C: Diesel Particulate Filter (DPF) High Temperature
Circuit/System Description
The exhaust gas temperature sensors are variable resistors that measure the temperature of the exhaust gas. The exhaust gas temperature sensor 1 is located in the exhaust manifold before the turbocharger. The exhaust gas temperature 2 sensor is located in the exhaust pipe after the turbocharger. The exhaust gas temperature 3 sensor is located in the exhaust gas particle filter. The engine control module (ECM) supplies 5 V to the exhaust gas temperature signal circuit and supplies a ground to the low reference circuit. The exhaust gas temperature sensor temperature information is used by the ECM during the exhaust gas particulate filter cleaning process.
The following table illustrates the difference between temperature, resistance, and voltage:
Exhaust Gas Temperature
| Exhaust Gas Temperature Resistance
| Exhaust Gas Temperature Signal Voltage
|
Cold
| High
| High
|
Warm
| Low
| Low
|
Conditions for Running the DTC
• | The DTC runs continuously when the above condition is met. |
Conditions for Setting the DTC
• | The ECM detects that the exhaust gas temperature sensor is less than 0.1 V for greater than 1 s or the exhaust gas temperature sensor is greater than 4.9 V for greater than 1 s. |
• | The ECM detects an invalid signal from the exhaust gas temperature sensor for greater than 1 s. |
Action Taken When the DTC Sets
DTC P200C a Type A DTC.
Conditions for Clearing the DTC
DTC P200C a Type A DTC.
Diagnostic Aids
• | After starting the engine, the exhaust gas temperature sensor temperature should rise steadily, then stabilise after the engine reaches operating temperature. |
• | If the vehicle has sat overnight, the exhaust gas temperature sensor and the intake air temperature (IAT) sensor values should display within 3°C (5°F). |
The following conditions can also cause the DTC to set:
• | Faulty air inlet system |
• | Faulty or plugged exhaust system, such as plugged diesel particulate filter |
• | Excessive oil consumption |
• | Engine misfire with excessive oil consumption |
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Ignition On, observe the DTC information with a scan tool. Verify no other DTCs are set.
- Engine running, observe the DTC information with a scan tool. DTCs P0545, P0546, P2080, P2081, P2085, P242B, P2428, P242C, P242D, P242D should not set.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
- Engine running, observe all exhaust gas temperature sensors temperature, the values should be nearly the same.
Circuit/System Testing
Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
- Ignition OFF, disconnect the harness connector at the B131C Exhaust Temperature Sensor 3.
- Test for less than 5 Ω between the low reference circuit terminal 2 and ground.
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
- Ignition ON, verify the scan tool Exhaust Gas Temperature Sensor 3 parameter is at 900°C (1 653°F).
⇒ | If less than the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module. |
Caution: If the fuse in the jumper wire opens, the signal circuit may have a short to a voltage or a short to ground and the sensor might be damaged.
- Install a 3 A fused jumper wire between the signal circuit terminal 1 and ground. Verify the scan tool Exhaust Gas Temperature Sensor 3 parameter is at -40°C (-40°F).
⇒ | If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module. |
Note: If the DTC still resets after temperature sensor replacement, take notice of the vehicle conditions under Diagnostic Aids.
- If all circuits test normal, test or replace the B131C Exhaust Temperature Sensor 3.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
© Copyright Chevrolet. All rights reserved |
© Copyright Chevrolet. All rights reserved |