Hino P2635 Fault Code: Supply Pump Low Flow/Performance

TECHNICAL DESCRIPTION

Excessively high common rail pressure (this duration varies depending on the engine speed) is detected.

DESCRIPTION OF MALFUNCTION

Supply pump was exposed to abnormally high pressure.

DTC SET CONDITION

DTC Detection Condition:

− Battery voltage is in the range of 10 V to 16 V.

− Common rail pressure sensor; no malfunction.

Judgment Criteria:

− Common rail pressure ≥ threshold map.

− 60 sec continue

RESET CONDITION

After normal operation is restored and the starter switch is on the “LOCK” position.

INDICATION, WARNING OR SYSTEM CONTROL REGULATION WHEN THE DTC IS SET

− MIL: OFF

− SVS light: OFF

PRE-INSPECTION WORK

Check that the battery voltage is in the normal range.

AFTER-INSPECTION WORK

− Clear all past DTCs.

− Check that no DTC is detected after test drive.

POSSIBLE CAUSES

− Supply pump failure.

− Malfunction of engine ECU.

INSPECTION PROCEDURE

TROUBLESHOOTING STEPS

Step 1) Inspect the start of the engine.

Inspect the start of the engine.

Did the engine start?

Step 2) Inspect the supply pump.

Check if fuel is leaking or seeping out of the supply pump.

Were any failures found?

Step 3) Function check of supply pump [Diagnostic Tool].

1. Connect the vehicle to the diagnostic tool.
2. Set the starter switch to the “ON” position.
3. Select [Engine].
4. Select [Actual common rail pressure] and [Target common rail pressure] in [Data monitor setting].
5. Start the engine while checking the common rail pressure

NOTE: Turn the starter switch OFF and ON verifies the wiping operation of the VNT actuator (DC motor).

Were any failures found?

Step 4) Check the engine ECU.

Check the engine ECU software part number (ECU part number) by the diagnostic tool. Confirm the latest part number with the OEM.

Does the engine ECU have the latest software number?

Step 5) Inspect the pre-fuel filter.

1. Check the pre-fuel filter.

− Has the replacement period expired?

− Is it dirty, damaged, or clogged?

− Is it a genuine OEM part?

2. Check if the fuel inside the pre-fuel filter is within the standard value.

Were any failures found?

Step 6) Inspect the fuel pipe and hose.

1. Check if the fuel pipe and hose between the fuel tank and fuel filter are clogged, punctured, or bent.
2. Make sure the fuel pipe joint bolts are not loose.

Were any failures found?

Step 7) Inspect the fuel tank breather.

1. Check if the breather hose is clogged, punctured, or bent.
2. Make sure the check valve is functioning normally.

Were any failures found?

Step 8) Inspect the fuel tank feed pipe.

Make sure the fuel tank feed pipe is not clogged.

Were any failures found?

Step 9) Inspect the fuel tank.

Drain fuel out of the fuel tank and check if there are foreign objects inside the tank.

Were any failures found?

Step 10) Inspect the supply pump gauze filter.

Make sure the gauze filter (built into the supply pump) is not clogged.

Were any failures found?

Step 11) Inspect the fuel high-pressure pipe.

Make sure the fuel high-pressure pipe is not leaking fuel.

Were any failures found?

Step 12) Inspect the fuel filter.

Make sure the fuel filter is not clogged.

Were any failures found?

Step 13) Inspect the SCV connector.

Check the connection of the SCV connector (Looseness or short-circuit).

Were any failures found?

Step 14) Inspect the common rail pressure sensor connector.

Check the connection of the common rail pressure sensor connector (Looseness or poor contact).

Were any failures found?

Step 15) Inspect the common rail pressure sensor power supply.

1. Disconnect the connector of the common rail pressure sensor.
2. Set the starter switch to the “ON” position.
3. Use the electrical tester to measure the voltage between the terminals of the common rail pressure sensor vehicle-side connector.

Do the measurements meet the standard value?

Step 16) Inspect the crankshaft position sensor (engine speed main sensor) [Diagnostic Tool].

1. Set the starter switch to the “ON” position.
2. Select [Engine].
3. Select [NE sensor active flag], [G sensor active flag] in [Data monitor setting].
4. Start the engine and confirm that the engine main speed sensor (NE) and sub speed sensor (G) operate (stay ON) continuously.

Were any failures found?

Step 17) Inspect the fuel return pipe and hose.

Check if the fuel return pipe and hose are clogged

Were any failures found?

ECUTools Vietnam

Whatsapp: +84.899.402.402

Facebook: ECUTools.vn

Youtube: ECUToolsvn

Tiktok: ECUTools

Website: ECUTools.vn