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Isuzu Rodeo UE. Manual - part 242

6E1–339

RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

DTC P1404 EGR Closed Valve

(Cont'd)

Step

Yes

Value(s)

Action

1. Ignition ON, engine OFF.
2. Using a Digital Voltmeter (DVM), check for voltage

on the 5 volt Reference signal circuit at the Linear
Exhaust Gas Recirculation (EGR) Valve wiring
harness connector.

Does the DVM read the following value?

about 5 volts

Go to Step 11

Go to Step 10

Check the 5 volt reference signal circuit, between the
EGR and the PCM, for the following conditions:

An Open circuit

A short to ground

Was the problem found?

—

Verify repair

Go to Step 11

1. Ignition OFF.
2. Place a DVM between the 5 volt reference signal

circuit and the 5 volt signal return (ground) circuit at
the EGR wiring harness connector.

3. Ignition ON, Engine OFF.

Does the DVM read the following value?

about 5 volts

Go to Step 13

Go to Step 12

Check the 5 volt signal return (ground) circuit, between
the EGR and the PCM, for the following conditions:

An Open circuit

A short to ground

Was the problem found?

—

Verify repair

Go to Step 15

1. Ignition OFF.
2. Place a fused jumper wire between the 5 volt

reference signal circuit and the EGR valve position
feedback circuit at the EGR wiring harness
connector.

3. Ignition ON, Engine OFF.
4. Observe the EGR value on the Tech 2.

Does the Tech 2 display the following value?

5 volts 100%

Go to Step 14

Go to Step 15

Replace the Linear Exhaust Gas Recirculation (EGR)
Value.
Verify repair.

—

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed. Refer to On–Vehicle Service in
Powertrain Control Module and Sensors for
procedures.

And also refer to latest Service Bulletin.
Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.

Verify repair.

—

6E1–340

RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

DIAGNOSTIC TROUBLE CODE (DTC) P1441 EVAPORATIVE EMISSION (EVAP)

SYSTEM FLOW DURING NON–PURGE

D06RX056

Circuit Description

Canister purge is controlled by a solenoid valve that
allows manifold vacuum to purge the canister. The
powertrain control module (PCM) supplies a ground to
energize the solenoid valve (purge ON). The EVAP purge
solenoid control is pulse–width modulated (PWM) and is
turned ON and OFF several times a second. The duty
cycle (pulse width) is determined by engine operating
conditions including load, throttle position, coolant
temperature and ambient temperature. The duty cycle is
calculated by the PCM and the output is commanded
when the appropriate conditions have been met.
The EVAP purge vacuum switch is a normally closed
switch positioned in the purge line between the canister
and the EVAP purge solenoid. The EVAP purge vacuum
switch will open when vacuum increases to greater than 5
inches of water pressure in the purge line. The PCM
monitors the EVAP purge vacuum switch signal to
determine if the evaporative emission control system is
working properly. If the switch is open (purge flow
detected) when the PCM is not commanding the EVAP
purge solenoid ON, DTC P1441 will be set. DTC P1441 is
a type A code.

Conditions for Setting the DTC

No active system voltage, ECT sensor, IAT sensor, VS
sensor, MAP sensor, vacuum switch, or TP sensor
DTCs set.

BARO reading is above 72.3 kPa.

Start–up intake air temperature (IAT) and start–up
engine coolant temperature(ECT) are both between
3.5

C (38

F) and 32

C (90

F).

The difference between start–up ECT and start–up IAT
is less than 6.75

C(12.2

F).

The Fuel Tank Level Sensor reads between 10% and
90%.

The vehicle speed is less than 98 km/h (60mph).

Fuel thank vacuum is greater than 15.25 cm (6 inches)
of water for 0.5 seconds.

Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.

Conditions for Clearing the MIL/DTC

The PCM will turn the MIL OFF on the third consecutive
trip cycle during which the diagnostic has been run and
the fault condition is no longer present.

A history DTC P1441 will clear after 40 consecutive
warm–up cycles have occurred without a fault.

DTC P1441 can be cleared by using the Scan Tool’s
”Clear Info” function.

6E1–341

RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

Diagnostic Aids

Check for the following conditions:

Poor connection at PCM – Inspect harness connectors
for backed–out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal–to–wire connection.

The Fuel Pressure Sensor shares a 5 Volt reference
with the MAP sensor and TP sensor.

If these codes are also set, it could indicate a
problem with the 5 Volt reference circuit or
components itself.

The Fuel Pressure Sensor share a ground with the
MAP sensor and the TP sensor.

Damaged harness – Inspect the wiring harness for
damage; shorts to ground, shorts to battery positive,
and open circuits. If the harness appears to be OK,
observe the EVAP vacuum switch display on the Tech
2 while moving connectors and wiring harnesses
related to the sensor. A change in the display will
indicate the location of the fault.

Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often

the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. The canister purge vacuum switch is normally

closed when no vacuum (purge) is present. With the
ignition ON and the engine OFF, there shouldn’t be
any vacuum (purge) present in the EVAP system.

3. Determines if the PCM is able to control the EVAP

purge solenoid valve.

4. Determines if the DTC will set under the conditions

present when the DTC was originally stored. If not,
the fault is intermittent.

5. Checks for a grounded EVAP purge solenoid driver

circuit, a faulty EVAP vacuum switch, or a leaking
EVAP purge solenoid valve.

DTC P1441 – EVAP System Flow During Non-Purge

Step

Action

Value(s)

Yes

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to

Step 2

Go to

OBD

System

Check

1. Ignition “OFF.”
2. Remove the fuel filler cap.
3. Ignition “ON.” Observe “Fuel Tank Pressure” on the

Tech 2.

Is “Fuel Tank Pressure” at the specified value?

1.51 V

Go to

Step 3

Go to

P0452

or P0453

1. Re–install the fuel filler cap.
2. Using the Tech 2, command the EVAP Vent

Solenoid Valve “ON” (Closed).

3. Disconnect the canister side rubber hose end that

hose is connected between the Purge Solenoid
Valve and Canister.

IMPORTANT: Before continuing with the diagnosis,
zero the EVAP pressure and vacuum gauges on EVAP
pressure / purge cart J41413 (refer to the tool operating
instructions).
And then monitor the fuel tank inner pressure using the
Tech 2.

Does the fuel tank pressure hold the specified value?

1.52 - 1.60 V

Go to

Step 4

Go to

Step 6

6E1–342

RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

DTC P1441 – EVAP System Flow During Non-Purge

(Cont'd)

Step

Yes

Value(s)

Action

1. Disconnect the EVAP pressure / purge cart J41413,

and then plug the hose end.

2. Disconnect the rubber hose end of engine vacuum

source side, (the hose connected between Purge
Solenoid Valve and engine).

3. Connect a vacuum hand pump to this rubber hose

end.

4. Then apply -15 in H2O vacuum by the vacuum

pump.

5. Monitor the fuel tank inner pressure using the Tech

Does the fuel tank inner pressure hold the specified
value?

1.47 - 1.51 V

Go to

Step 6

Go to

Step 5

Replace the Purge Solenoid Valve.

—

Verify repair

—

1. Check for leaks, kinks or pinched hoses at the

EVAP system rubber hose line, and also check if the
rubber hoses are correctly connected or not.

2. Check for a leak from Vent Solenoid Valve and

EVAP system rubber hoses, and also check for
clogged Filter of air separator which is located near
the vent solenoid valve.

Was a problem found? Using the Vacuum Hose
Routing Diagram, repair or re-connect the rubber
hoses correctly.

—

Verify repair

Go to

Step 7

1. Start engine.
2. Remove the Fuel Filler Cap.
3. Using the Tech 2, command the EVAP Vent

Solenoid Valve “ON” (closed) and Purge Solenoid
Valve “OFF” (0%).

4. Replace the Fuel Filler Cap.
5. Run the engine at 2500RPM constant while

monitoring “Fuel Tank Vacuum” on the Tech 2.

Does the fuel tank vacuum remain at the specified
value while the EVAP Vent Solenoid Valve “ON”
(closed) and Purge Solenoid Valve “OFF” (o%)?

30 - 40%

Verify repair

Go to

Diagnostic

Aids

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