Code No. P2455: Exhaust Differential Pressure Sensor Circuit High Input

A power voltage of 5 V is applied to the exhaust differential pressure sensor power terminal from the engine-ECU connector terminal DDP5 and earthed to the engine-ECU connector terminal DDPE from the exhaust differential pressure sensor connector terminal.
The sensor signal is inputted to the engine-ECU connector terminal DDPS from the exhaust differential pressure sensor output terminal.

The exhaust differential pressure sensor outputs the voltage to the engine-ECU in accordance with the difference in the voltage between the DPF upstream area and the DPF down stream area.
The engine-ECU anticipates the amount of PM accumulated in the DPF through this output voltage.

Check Conditions

Battery positive voltage is 8 - 16 V
2 seconds later after the ignition switch has been in "ON" position or the engine has started up

Judgement Criterion

Failed exhaust differential pressure sensor
Open circuit in exhaust differential pressure sensor circuit or loose connector contact
Failed engine-ECU

DIAGNOSIS PROCEDURE

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).

	Go to Step 2.

(1)Disconnect the connector, and measure at the wiring harness side.

(2)Check the resistance between the exhaust differential pressure sensor connector (DDPE line) and body earth.
OK: Continuity (2 Ω or less)

	Go to Step 5.

	Go to Step 3.

	Go to Step 4.

	Repair the connector(s) or wiring harness.

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).

	Replace the engine-ECU.

After replacing the exhaust differential pressure sensor, Carry out the forcible DPF regeneration. (Refer to GROUP 17 - Emission Control <DIESEL> - Diesel Particulate Filter (DPF) System - Forcible DPF Regeneration ). After carrying out the forcible DPF regeneration, reconfirm diagnosis code.

	Go to Step 4.

	Check end.