Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 1442

9.

ENGINE CONTROL MODULE (ECM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Exhaust Differential
Pressure Sensor and the Engine Control Module (ECM).

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals.

Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.

Look for the data to change or for the DTC to reset during the wiggle test.

Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

>> Repair as necessary.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

No

>> Replace the Engine Control Module (ECM) in accordance with the Service Information.

Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

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P2454-DIESEL PARTICULATE FILTER DIFFERENTIAL PRESSURE SENSOR CIRCUIT
LOW

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For a complete wiring diagram Refer to Section 8W

Theory of Operation

The Diesel particulate filter is an inline canister filter located in the exhaust system between the engine and the
muffler. This filter captures and stores ash particles created by the diesel combustion process. This filter is moni-
tored by the ECM with a Differential Pressure Sensor. This sensor measures the difference in exhaust system pres-
sure before and after the particulate filter through tube connections directly to the exhaust pipe. As ash accumulates
in the filter, the exhaust pressure at the inlet side of the filter increases as compared to the pressure at the outlet
side of the filter. The ECM monitors the sensor to determine when to perform a particulate filter regeneration pro-
cedure which is designed to clear or “burn-off” the ash collected in the filter.

•

When Monitored:
With the ignition on.

•

Set Condition:
The (K355) Exhaust Differential Pressure Sensor signal is below 0.24 volts for 2.0 seconds.

Possible Causes

INTERMITTENT DTC

(K354) EXHAUST DIFFERENTIAL PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND

(K355) EXHAUST DIFFERENTIAL PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND

(K354) EXHAUST DIFFERENTIAL PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT SHORTED TO (K951)
EXHAUST DIFFERENTIAL PRESSURE SENSOR GROUND CIRCUIT

(K355) EXHAUST DIFFERENTIAL PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO (K951) EXHAUST
DIFFERENTIAL PRESSURE SENSOR GROUND CIRCUIT

(K354) EXHAUST DIFFERENTIAL PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT OPEN OR HIGH
RESISTANCE

(K355) EXHAUST DIFFERENTIAL PRESSURE SENSOR SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE

EXHAUST DIFFERENTIAL PRESSURE SENSOR

ENGINE CONTROL MODULE (ECM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)

Diagnostic Test

1.

DTC IS ACTIVE

Ignition on, engine not running.

With the scan tool, Clear DTCs in the Engine Control Module (ECM).

Monitor the scan tool for at least two minutes.

Cycle the ignition key off and on several times, leaving the ignition on for at least 10 seconds at a time.

Start the engine.

Allow the engine to reach normal operating temperature.

With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

>> Go To 2

No

>> Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE -

DIAGNOSIS AND TESTING)

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2.

(K354) EXHAUST DIFFERENTIAL PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT VOLTAGE

Turn the ignition off.

Disconnect the Exhaust Differential Pressure Sensor connector.

Turn the ignition on.

Measure the voltage of the (K354) Exhaust Differential Pressure Sensor
5 Volt Supply circuit in the Exhaust Differential Pressure Sensor har-
ness connector.

Is the voltage above 4.5 volts?

Yes

>> Go to 6

No

>> Go to 3

3.

(K354) EXHAUST DIFFERENTIAL PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND

Turn the ignition off.

Disconnect the Engine Control Module (ECM) connector.

Measure the resistance between ground and the (K354) Exhaust Differ-
ential Pressure Sensor 5 Volt Supply circuit in the Exhaust Differential
Pressure Sensor harness connector.

Is the resistance above 1000 ohms?

Yes

>> Go to 4

No

>> Repair the (K354) Exhaust Differential Pressure Sensor 5

Volt Supply circuit for a short to ground.

Perform the ECM Verification Test Ver. 1 (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).

4.

(K354) EXHAUST DIFFERENTIAL PRESSURE SENSOR 5 VOLT SUPPLY CIRCUIT SHORTED TO (K951)
EXHAUST DIFFERENTIAL PRESSURE SENSOR GROUND CIRCUIT

Measure the resistance between the (K354) Exhaust Differential Pres-
sure Sensor 5 Volt Supply circuit and the (K951) Exhaust Differential
Pressure Sensor Ground circuit in the Exhaust Differential Pressure
Sensor harness connector.

Is the resistance above 1000 ohms?

Yes

>> Go to 5

No

>> Repair the (K354) Exhaust Differential Pressure Sensor 5

Volt Supply circuit for a short to the (K951) Exhaust Differ-
ential Pressure Sensor Ground circuit.

Perform the ECM Verification Test Ver. 1 (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).

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