Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 1247

6E1–64

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

D

Damaged harness – Inspect the wiring harness for
damage; shorts to ground, shorts to battery voltage,
and open circuits. If the harness appears to be OK,
observe the A/C clutch while moving connnectors and
wiring harnesses related to the A/C. A sudden clutch
malfunction will indicate the source of the intermittent.

A/C Clutch Diagnosis

This chart should be used for diagnosing the electrical
portion of the A/C compressor clutch circuit. A Tech 2 will

be used in diagnosing the system. The Tech 2 has the
ability to read the A/C request input to the PCM. The Tech
2 can display when the PCM has commended the A/C
clutch ON. The Tech 2 should have the ability to override
the A/C request signal and energize the A/C compressor
relay.

A/C Clutch Control Circuit Diagnosis

 

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.
2. Review and record Tech 2 Failure Records data,

then clear the DTCs.

3. Operate the vehicle within the Failure Records

conditions as noted.

4. Using the Tech 2, monitor ”DTC” info for DTC

P1546.

Does the Tech 2 indicate DTC P1546 ”Ran and
Passed”?

—

Refer to

Diagnostic

Aids 

Go to 

Step 3 

3

1. Ignition OFF.
2. Remove the A/C Compressor Relay from the

Underhood Electrical Center.

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

on the Fused pins of the A/C Compressor Clutch
Relat connector.

Does the DVM read the following value?

12 Volts

Go to 

Step 5 

Go to 

Step 4 

4

Check the suspect circuit(s) between the A/C
Compressor Clutch Relay connector and the Fuse for
the following conditions:

D

A short to ground

D

An open circuit

D

A short to voltage

Was the problem found?

—

Verify repair

—

5

1. Ignition OFF.
2. Disconnect the Powertrain Controlm Module (PCM)

connectors from the PCM.

3. Check the A/C Compressor Clutch Relay control

circuit between the PCM and Underhood Electrical
Center for the following conditions:

D

A short to ground

D

An open circuit

D

A short to voltage

Was the problem found?

—

Verify repair

Go to 

Step 6 

6E1–65

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

A/C Clutch Control Circuit Diagnosis

  (Cont'd)

Step

No

Yes

Value(s)

Action

6

1. Reinstall the A/C Compressor Clutch Relay.
2. Using a fused jumper, ground the A/C Compressor

Clutch Relay control circuit at the PCM connector.

3. Ignition ON, engine OFF.

Does the A/C Compressor turn ON?

—

Go to 

Step 9 

Go to 

Step 7 

7

1. Ignition OFF.
2. Check the A/C Compressor Clutch circuit between

the A/C Compressor Clutch Relay and A/C
Compressor Clutch for the following conditions:

D

A short to ground

D

An open circuit

D

A short to voltage

Was the problem found?

—

Verify repair

Go to 

Step 8 

8

Replace the A/C Compressor Clutch Relay.

Is the action complete?

—

Verify repair

—

9

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.

—

—

—

6E1–66

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

ELECTRONIC IGNITION SYSTEM

DIAGNOSIS

If the engine cranks but will not run or immediately stalls,
the Engine Cranks But Will Not Start chart must be used
to determine if the failure is in the ignition system or the
fuel system. If DTC P0300, P0341, P0342, or P0336 is
set, the appropriate diagnostic trouble code chart must be
used for diagnosis.
If a misfire is being experienced with no DTC set, for
diagnosis, refer to the Symptoms section.

EVAP CANISTER PURGE SOLENOID

A continuous purge condition with no purge commanded
by the PCM will set a DTC P1441. A fault (small leak) in
the EVAP purge vacuum system will set a DTC P0442.
Refer to the DTC charts for further information.

VISUAL CHECK OF THE

EVAPORATIVE EMISSION CANISTER

014RX001

D

If the canister is cracked or damaged, replace the
canister.

D

If fuel is leaking from the canister, replace the canister
and check hoses and hose routing.

IDLE AIR CONTROL (IAC) VALVE

0006

The Tech 2 displays the IAC pintle position in counts. A
count of ”0” indicates the PCM is commanding the IAC
pintle to be driven all the way into a fully–seated position.
This is usually caused by a vacuum leak.
The higher the number of counts, the more air is being
commanded to bypass the throttle blade. In order to
diagnose the IAC system, refer to IAC System Check.
For other possible causes of idle problems, refer to
Rough, Unstable, or Incorrect Idle, Stalling in Symptoms.

FUEL SYSTEM PRESSURE TEST

A fuel system pressure test is part of several of the
diagnostic charts and symptom checks. To perform this
test, refer to Fuel System Diagnosis.

6E1–67

RODEO Y22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

FUEL METERING SYSTEM CHECK

Some failures of the fuel metering system will result in an
”Engine Cranks But Will Not Run” symptom. If this
condition exists, refer to the Cranks But Will Not Run
chart. This chart will determine if the problem is caused by
the ignition system, the PCM, or the fuel pump electrical
circuit.
For the fuel system wiring schematic, refer to Fuel
System Electrical Test.
If there is a fuel delivery problem, to diagnose the fuel
injectors, the fuel pressure regulator, and the fuel
pump,refer to Fuel System Diagnosis.
If a malfunction occurs in the fuel metering system, it
usually results in either a rich HO2S signal or a lean HO2S
signal. This condition is indicated by the HO2S voltage,
which causes the PCM to change the fuel calculation (fuel
injector pulse width) based on the HO2S reading.
Changes made to the fuel calculation will be indicated by
a change in the long term fuel trim values which can be
monitored with a Tech 2. Ideal long term fuel trim values
are around 0%; for a lean HO2S signal, the PCM will add
fuel, resulting in a fuel trim value above 0%. Some
variations in fuel trim values are normal because all
engines are not exactly the same. If the evaporative
emission canister purge is ON, the long term fuel trim may
be as low as –38%. If the long term fuel trim values are
greater than +23%, for items which can cause a lean
HO2S signal, refer to DTC P0131,   DTC P0171, and DTC
1171.

FUEL INJECTOR COIL TEST

PROCEDURE AND FUEL INJECTOR

BALANCE TEST PROCEDURE

T32003

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Relieve the fuel pressure by connecting the J

34730–1 Fuel Pressure Gauge to the fuel pressure
connection on the fuel rail.

CAUTION: In order to reduce the risk of fire and
personal injury, wrap a shop towel around the fuel
pressure connection. The towel will absorb any fuel
leakage that occurs during the connection of the fuel
pressure gauge. Place the towel in an approved
container when the connection of the fuel pressure
gauge is complete.

Place the fuel pressure gauge bleed hose in an
approved gasoline container.
With the ignition switch OFF open the valve on the
fuel pressure gauge.

3.Record the lowest voltage displayed by the DVM

after the first second of the test. (During the first
second, voltage displayed by the DVM may be
inaccurate due to the initial current surge.)

Injector Specifications:

Resistance Ohms

Voltage Specification at

10

°

C–35

°

C (50

°

F–95

°

F)

11.8 – 12.6

5.7 – 6.6

D

The voltage displayed by the DVM should be within
the specified range.

D

The voltage displayed by the DVM may increase
throughout the test as the fuel injector windings
warm and the resistance of the fuel injector windings
changes.

D

An erratic voltage reading (large fluctuations in
voltage that do not stabilize) indicates an
intermittent connection within the fuel injector.

5. Injector Specifications:

Highest Acceptable Voltage

Reading Above/Below

35

°

C/10

°

C  (95

°

F/50

°

F)

Acceptable

Subtracted Value

9.5 Volts

0.6 Volt

7. The Fuel Injector Balance Test portion of this chart

(Step 7 through Step 11) checks the mechanical
(fuel delivery) portion of the fuel injector. An engine
cool–down period of 10 minutes is necessary in
order to avoid irregular fuel pressure readings due
to ”Hot Soak” fuel boiling.