Isuzu Rodeo UE. Manual - part 387

6E2–303

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0356 – Ignition 6 Control Circuit

  (Cont'd)

Step

No

Yes

Value(s)

Action

11

Check for an open ignition control circuit 6.

Was the ignition control circuit open?

—

Go to 

Step 12

Go to 

Step 13

12

Repair the open ignition control circuit.

Is the action complete?

—

Verify repair

—

13

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

—

6E2–304

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0401 EGR Flow Insufficient

D06RW055

Circuit Description

The powertrain control module (PCM) tests the exhaust
gas recirculation (EGR) system during deceleration by
momentarily commanding the EGR valve to open while
monitoring the manifold absolute pressure (MAP) sensor
signal.  When the EGR valve is opened, the PCM
monitors the change in MAP input signal.  The PCM
compares the MAP change to a RPM vs. BARO table.
When the PCM interprets the change in MAP to be out of
limits, the PCM will set DTC P0401.  The number of test
samples required to accomplish this may vary according
to the severity of the detected flow error.
Normally, the PCM will only allow one EGR flow test
sample to be taken during an ignition cycle.  To aid in
verifying a repair, the PCM allows twelve test samples
during the first ignition cycle following a Tech 2 “Clear Info”
or a battery disconnect.  Between nine and twelve
samples should be sufficient for the PCM to determine
adequate EGR flow and pass the EGR test.

Conditions for Setting the DTC

f

No TP sensor, vehicle speed sensor (VSS), misfire,
IAC, IAT sensor, MAP sensor, EGR Pintle Position
sensor, ECT sensor, misfire, or automatic
transmission DTCs set.

f

Barometric pressure is above 75 kPa.

f

Engine coolant temperature is greater than 60

°

C

(140

°

F).

f

Ignition voltage between 11.5 and 16 volts.

f

Vehicle speed is greater than 24 km/h (15 mph).

f

IAC position is steady, changing less than 10 counts.

f

A/C clutch status is unchanged.

f

TCC status is unchanged.

Start Test

f

TP angle is less than 1%.

f

EGR duty cycle is less than 1%.

f

MAP is steady, changing less than 2 kPa.

f

Engine speed is between 1100 RPM and 2000 RPM.

f

MAP between 10 kPa and 40 kPa.

The test will be aborted if the vehicle speed changes by
more than 16 km/h (10 mph), engine speed changes by
more than 100 RPM or the EGR is opened less than 95%
of commanded position.

f

The PCM will only run the EGR test during a closed
throttle condition.

f

The PCM will only run the EGR test at vehicle speeds
above 24 km/h (15 mph).

f

Several deceleration cycles will be necessary to run a
sufficient number of EGR flow tests.

Diagnostic Aids

Check for the following conditions:

f

Poor connection or damaged harness – Inspect the
wiring harness for damage.  If the harness appears to
be OK, observe the Actual EGR Position display on the
Tech 2 while moving connectors and wiring harnesses

6E2–305

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

related to the EGR valve.  A change in the display will
indicate the location of the fault.

f

Ensure EGR valve is correctly mounted.  See
On-Vehicle Service.

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.

NOTE: If the EGR valve shows signs of excessive heat,
check the exhaust system for blockage (possibly a
plugged catalytic converter) using the “Restricted
Exhaust System Check.”

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart
3. A malfunctioning MAP sensor can set an EGR DTC.

The MAP sensor could send a constant signal which
is not low enough to set a low MAP DTC.  The
constant signal from the MAP sensor also may not
be high enough to set a high MAP DTC. This step
verifies that the MAP sensor is responding.

6E2–306

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0401 – EGR Flow Insufficient

 

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

Is DTC P1406 also set?

—

Go to 

DTC

1406

Go to 

Step 3

3

1. Start the engine.
2. Monitor the MAP signal with a Tech 2 while idling.
3. While idling, jab the accelerator pedal about halfway

down and immediately let the engine return to idle.

Did the MAP value on the Tech 2 show an immediate
large change?

—

Go to 

Step 5

Go to 

Step 4

4

Replace the MAP sensor.

Is the action complete?

—

Verify repair

—

5

1. Inspect the exhaust system for modification of

original installed parts or leaks.

2. If a problem was found, repair exhaust system as

necessary.

Was a condition present that required repair?

—

Go to 

Step 8

Go to 

Step 6

6

1. Remove the EGR valve.
2. Visually and physically inspect the pintle, valve

passages and the adapter for excessive deposits or
any kind of a restriction.

3. If a problem is found, clean or replace EGR system

components as necessary.

Was a condition present that required repair?

—

Go to 

Step 8

Go to 

Step 7

7

1. Remove the EGR inlet and outlet pipes from the

exhaust manifold and the intake manifold.

2. Inspect the manifold EGR ports and the EGR inlet

and outlet pipes for a blockage caused by excessive
deposits or other damage.

3. If a problem is found, correct the condition as

necessary.

Was a condition present that required repair?

—

Go to 

Step 8

Refer to

Diagnostic

Aids

8

1. Review and record the Tech 2 Failure Records data.
2. Clear DTC and monitor the Tech 2 System Info

Screen while operating the vehicle as specified in
“Diagnostic Aids.”

3. Using a Tech 2, monitor “DTC” info for DTC P0401

until the DTC P0401 test runs.

4. Note the test result.

Does the Tech 2 indicate DTC P0401 failed this
ignition?

—

Go to

Diagnostic

Aids

Repair

complete