Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 361

6E–474

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P1404 EGR Stuck Closed

060R200050

Circuit Description

The powertrain control module (PCM) monitors the EGR
valve pintle position input to ensure that the valve
responds properly to commands from the PCM, and to
detect a fault if current pintle zero position is different from
the learned zero position. If the PCM detects a pintle
position signal indicates more than 30 % different
between current zero position and the learned zero
position for more than 5 seconds, and this condition exists
3 times during trip, then the PCM will set DTC P1404.

Conditions for Setting the DTC

D

Ignition voltage is between 11 and 16 volts.

D

Intake Air temp is more than 3

°

C.

D

Desired EGR position is more than 3 %.

D

Difference of EGR pintle position between current and
the learned zero is more than 30 % for more than 5
seconds, and exists three times to the above condition
during  a trip the PCM will set DTC 1404. Then it trigger
the PCM light on.

Action Taken When the DTC Sets

D

The PCM will illuminate the malfunction indicator lamp
(MIL) after consecutive 2nd trip in which the fault is
detected.

D

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

Conditions for Clearing the MIL/DTC

D

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.

D

A history DTC P1404 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P1404 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

Excessive carbon deposit on EGR valve shaft and/or
foreign material  may cause the EGR valve not to fully
seat. The carbon deposit may occur by unusual port
operation. Remove foreign material and/or excessive
carbon deposit on EGR valve shaft and to allow the
EGR valve to be fully seated.

D

Poor connection or damaged harness – Inspect the
wiring harness for damage.

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.

6E–475

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1404 – EGR Stuck Closed

 

Step

Action

Value(s)

Yes

No

1

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

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “ON”, engine “OFF”, review and record

Tech 2 Failure Records Data.

2. Operate the vehicle within Failure Records

conditions as noted.

3. Using a Tech 2, monitor “DTC inf.” for DTC P1404

until the DTC P1404 test runs. Note the result.

Does the Tech 2 indicates DTC P1404 failed this
ignition?

—

Go to 

Step 3

Refer to

Diagnostic

Aids

3

1. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged

pin or terminals.

Were there any damaged pins or terminals?

—

Go to 

Step 4

Go to 

Step 5

4

Repair the damaged pin or terminal.

Is the action complete?

—

Verify repair

—

5

1. Remove EGR valve from Engine.
2. Inspect EGR valve for any excessive carbon

deposit on EGR shaft.

3. Inspect for any foreign material inside of EGR valve.

Was excessive carbon deposit on EGR valve shaft
and/or foreign material in EGR valve ?

—

Go to 

Step 6

Go to 

Step 7

6

1. Clean up EGR valve shaft and inside of EGR valve.
2. Remove foreign material from EGR valve.
3. Visually inspect damage of pintle and seat to see if it

is bent. If damaged, leakage may occur. 

Was there any severe damage which affects function?

—

Go to 

Step 9

Verify repair

Go to 

Step 7

7

1. Install the EGR valve.
2. Ignition “OFF”.
3. Install the Tech 2.
4. Run the engine at idle.
5. On the Tech 2, select EGR Control Test.
6. Use the “UP” arrow to increase the EGR from 0% to

40%.

Did EGR work properly?

—

Verify repair

Go to 

Step 8

8

1. Reset the learned zero EGR valve position.
2. Repeat step 7.

Did EGR work properly?

—

Verify repair

Go to 

Step 9

6E–476

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P1404 – EGR Stuck Closed

  (Cont'd)

Step

No

Yes

Value(s)

Action

9

Replace the EGR valve.

Does DTC P1404 still fail “DTC” test on the Tech 2?

—

Go to 

Step 10

Verify repair

10

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.

Is the action complete?

—

Verify repair

—

6E–477

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) 

P1441 EVAP System Flow During Non-Purge

060RY00398

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)
or 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.

Conditions for Setting the DTC

D

No active ECT sensor, IAT sensor, MAP sensor, or TP
sensor DTCs set.

D

BARO reading is above 85 kPa.

D

Engine coolant temperature is below 70

°

C (158

°

F).

D

Start-up intake air temperature (IAT) and start-up
engine coolant temperature (ECT) are both above 5

°

C

(41

°

F).

D

The difference between start-up ECT and start-up IAT
is less than 25

°

C (45

°

F).

D

TP sensor indicates a throttle position above 12%.

D

Battery voltage is between 11.5 volts and 16 volts.

D

Engine speed is between 800 and 6,000 RPM.

D

Canister purge duty cycle is below 3%.

D

Fuel level is between 15% and 85%.

D

All conditions are present for at least 3 seconds.

Action Taken When the DTC Sets

D

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

D

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

D

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.

D

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

D

DTC P1441 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

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.

D

Damaged harness – Inspect the wring harness for
damage. A change in the display will indicate the
location of the fault.