2002 ISUZU AXIOM clutch

6E±14
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
PCM Pinouts
PCM Pinout Table, 80-Way Blue Connector ± Row ªF1 ~ 20º
060RY00045
PINPIN FunctionWire ColorIGN ONENG RUNRefer To
F1PCM GroundBLK0.0V0.0VChassis Electrical
F25Volt Referenceª2º (AP
Sensor 2)GRN5.0V5.0VAccelerator Position (AP)
Sensor
F35Volt Referenceª2º (TP
Sensor 2)RED/WHT5.0V5.0VThrottle Position (TP) Sensor
F4A/C ClutchGRY/REDB+(A/C off)B+(A/C off)General Description and
Operation, A/C Clutch Circuit
Operation
F5Relay Shift SolenoidGRN/RED0.0V0.0V4L30E T/Mission
F6Not UsedÐÐÐÐ
F7TachometerBLK/RED8.8V10.0V (at
idle)Chassis Electrical
F8Not UsedÐÐÐÐ
F9Not UsedÐÐÐÐ
F10Not UsedÐÐÐÐ
F11T.O.DRED/WHTÐÐÐ
F12Not UsedÐÐÐÐ
F13Starter FeedPNKÐÐÐ
F14Mass Air Flow(MAF)BLK/BLU4.9V4.2VGeneral Description, Mass
Air Flow Sensor
F15Not UsedÐÐÐÐ
F16Not UsedÐÐÐÐ
F17Bank 1 HO2S LowRED0.3V0.1±0.9VGeneral Description and
Operation, Catalyst Monitor
HO2S 2
F18Not UsedÐÐÐÐ
F19Ignition FeedRED/GRNB+B+6D Section
F20Ignition FeedRED/WHTB+B+6D Section

6E±46
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Relays Test
This test is conducted to check Fuel Pump Relay and A/C
Clutch for proper operation.
Tech 2 must be used for this test.
Test Procedure:
1. Connect Tech 2 to the vehicle DLC.
2. Ignition SW is ªOnº.
3. Select F3: Miscellaneous Test in the Application
Menu.
060R100078
4. Select F1:Relay Test in the Miscellaneous Test.
060RY00081
5. Select F0:Fuel Pump Relay.
060RX021
6. Push ªOnº soft key.
060RY00093
7. Control Fuel Pump Relay and check data list.
8. If the data list changes, the Fuel Pump Relay is
normal.
9. Select F1:A/C Clutch Relay.
10. Run the Engine at idle.

6E±47
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
11. Turn on Air Conditioning.
060RY00094
12. Turn ªOnº and ªOffº A/C Switch.
13. Contol A/C Clutch Relay and check data list.
14. If the data list changes, the Fuel Pump Relay is
normal.
EVAP Test
This test is conducted to check EVAP system for its power
operation.
Tech 2 must be used for this test.
Test Procedure:
1. Connect Tech 2 to the vehicle DLC.
2. Run the Engine at idle.
3. Select F3: Miscellaneous Test in the Application
Menu.
060R100078
4. Select F2: EVAP Test in the Miscellaneous Test.
060RY00082
5. Select F0: Purge Solenoid.
060RX025

6E±63
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
A/C Clutch Control Circuit Diagnosis
060R100063
Circuit Description
When air conditioning and blower fan are selected, and if
the system has a sufficient refrigerant charge, a 12-volt
signal is supplied to the A/C request input of the
powertrain control module (PCM). The A/C request
signal may be temporarily canceled during system
operation by the electronic thermostat in the evaporator
case. When the A/C request signal is received by the
PCM, the PCM supplies a ground from the compressor
clutch relay if the engine operating conditions are within
acceptable ranges. With the A/C compressor relay
energized, voltage is supplied to the compressor clutch
coil.
The PCM will enable the compressor clutch to engage
whenever A/C has been selected with the engine running,
unless any of the following conditions are present:

The throttle is greater than 90%.

The ignition voltage is below 10.5 volts.

The engine speed is greater than 4500 RPM for 5
seconds or 5400 RPM.
The engine coolant temperature (ECT) is greater
than 125
C (257
F).

The intake air temperature (IAT) is less than 5
C
(41
F).

The power steering pressure switch signals a high
pressure condition.
Diagnostic Aids
To diagnose an the intermittent fault, check for following
conditions:

Poor connection at the PCM±Inspect connections for
backed-out terminals, improper mating, broken locks,
improperly formed or damaged terminals, and poor
terminal-to-wire connection.

Damaged harness±Inspect the wiring harness for
damage. If the harness appears to OK, observe the
A/C clutch while moving connectors and wiring
harnesses related to the A/C. A sudden clutch
malfunction will indicate the source of the intermittent
fault.

6E±64
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
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 commanded the
A/C clutch ªONº. The Tech 2 should have the ability to
override the A/C request signal and energize the A/C
compressor relay.
Test Description
IMPORTANT:Do not engage the A/C compressor
clutch with the engine running if an A/C mode is not
selected at the A/C control switch.
The numbers below refer to the step numbers on the
Diagnostic Chart:3. This a test determine is the problem is with the
refrigerant system. If the switch is open, A/C
pressure gauges will be used to determine if the
pressure switch is faulty or if the system is partially
discharged or empty.
4. Although the normal complaint will be the A/C clutch
failing to engage, it is possible for a short circuit to
cause the clutch to run when A/C has not been
selected. This step is a test for that condition.
7. There is an extremely low probability that both relays
will fail at the same time, so the substitution process
is one way to check the A/C Thermostat relay. Use
a known good relay to do a substitution check.
A/C Clutch Control Circuit Diagnosis

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Are any other DTCs stored?
Ð
Go to the
other DTC
chart(s) first
Go to Step 3
31. Disconnect the electrical connector at the pressure
switch located on the receiver/drier.
2. Use an ohmmeter to check continuity across the
pressure switch.
Is the pressure switch open?
Ð
Go to Air
Conditioning
to diagnose
the cause of
the open
pressure
switch
Go to Step 4
4IMPORTANT:Before continuing with the diagnosis, the
following conditions must be met:

The intake air temperature must be greater than
15
C. (60
F).

The engine coolant temperature must be less
than 119
C (246
F).
1. A/C ªOFFº.
2. Start the engine and idle for 1 minute.
3. Observe the A/C compressor.
Is the A/C compressor clutch engaged even though
A/C has not been requested?
ÐGo to Step 37Go to Step 5
51. Idle the engine.
2. A/C ªONº.
3. Blower ªONº.
4. Observe the A/C compressor.
Is the A/C compressor magnetic clutch engaged?
Ð
Refer to
Diagnostic
Aids
Go to Step 6
61. Engine idling.
2. A/C ªONº.
3. Blower ªONº.
4. Observe the ªA/C Requestº display on the Tech 2.
(Refer to the Miscellaneous test)
Does the tool ªA/C Requestº display indicate ªYesº?
ÐGo to Step 26Go to Step 7

6E±65
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
A/C Clutch Control Circuit Diagnosis

 
StepNo Ye s Value(s) Action
7Temporarily substitute the A/C compressor relay in
place of the A/C thermostat relay, then repeat Step 5.
Did the ªA/C Requestº display indicate ªYesº?
ÐGo to Step 8Go to Step 9
8Replace the original A/C thermostat relay.
Is the action complete?
ÐVerify repairÐ
9Does the blower operate?ÐGo to Step 10Go to Step 11
10Repair the blower.
Is the action complete?
ÐVerify repairÐ
11Check for a faulty 10A A/C fuse in the underdash fuse
panel.
Was the 10A fuse OK?
ÐGo to Step 13Go to Step 12
12Check for short circuit and make repairs if necessary.
Replace the 10A A/C fuse.
Is the action complete?
ÐVerify repairÐ
131. Remove the glove box to gain access to the A/C
thermostat.
2. Disconnect the thermostat connector.
3. Attach a fused jumper between ground and the
thermostat wire.
4. A/C ªONº.
5. Blower ªONº.
Dose A/C request indicate ªYESº on the Tech 2?
ÐGo to Step 14Go to Step 17
141. Ignition ªONº.
2. Use a DVM to check voltage at the electronic A/C
thermostat.
Was voltage equal to the specified value?
B+Go to Step 17Go to Step 15
15Check for open wire between the thermostat and the
A/C switch.
Was the wire open?
ÐGo to Step 16Go to Step 17
16Repair the open wire between the thermostat and the
A/C switch.
Is the action complete?
ÐVerify repairÐ
17Check for an open circuit between A/C thermostat relay
and PCM A/C request terminal (F45).
Was there an open circuit?
ÐGo to Step 18Go to Step 19
18Repair the open circuit between the PCM and A/C
thermostat relay.
Is the action complete?
ÐVerify repairÐ
191. Ignition ªONº.
2. Use a DVM to check voltage at the A/C pressure
switch.
Was voltage equal to the specified value?
B+Go to Step 21Go to Step 20
20Repair the open circuit between the 10A A/C fuse and
the pressure switch.
Is the action complete?
ÐVerify repairÐ

6E±66
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
A/C Clutch Control Circuit Diagnosis

 
StepNo Ye s Value(s) Action
21Use an ohmmeter to check continuity between the
pressure switch and the A/C thermostat relay.
Was the circuit open?
ÐGo to Step 22Go to Step 23
22Repair the open circuit between the pressure switch
and the A/C thermostat relay.
Is the action complete?
ÐVerify repairÐ
23Check for damaged pin or terminal at F45 of the PCM.
Was a damaged pin or terminal found?
ÐGo to Step 24Go to Step 25
24Repair the damaged pin or terminal.
Is the action complete?
ÐVerify repairÐ
25Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module 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?
ÐVerify repairÐ
261. Remove the A/C compressor relay.
2. Ignition ªONº.
3. Use a DVM to check voltage at both of the wires at
the A/C compressor relay socket.
Is the voltage equal to the specified value?
B+Go to Step 28Go to Step 27
27Repair the faulty wire between the A/C fuse and the
A/C compressor relay .
Is the action complete?
ÐVerify repairÐ
281. A/C compressor relay removed.
2. Engine idling.
3. A/C ªONº.
4. Blower ªONº.
5. Use a DVM to measure voltage between the wire at
the A/C compressor relay socket and battery+.
Did the DVM indicate the specified value?
B+Go to Step 32Go to Step 29
29Check for an open wire between PCM terminal F4 and
the A/C compressor relay.
Was the wire open?
ÐGo to Step 30Go to Step 31
30Repair the open wire between the PCM and the A/C
compressor relay.
Is the action complete?
ÐVerify repairÐ
31Check for a damaged pin or terminal at F4 of the PCM.
Was a damaged pin or a terminal found?
ÐGo to Step 24Go to Step 25

6E±67
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
A/C Clutch Control Circuit Diagnosis

 
StepNo Ye s Value(s) Action
321. A/C compressor relay removed.
2. Connect a fused jumper at the A/C compressor
relay socket with either wire.
3. Engine idling.
4. A/C ªONº.
5. Blower ªONº.
Did the compressor magnetic clutch engage?
ÐGo to Step 33Go to Step 34
33Repair the A/C compressor relay.
Is the action complete?
ÐVerify repairÐ
34Check for an open circuit between the A/C compressor
relay and the A/C clutch.
Was an open circuit found?
ÐGo to Step 35Go to Step 36
35Repair the open circuit between the compressor Clutch
and the A/C compressor relay.
Is the action complete?
ÐVerify repairÐ
36Service the compressor clutch or replace the
compressor due to a faulty internal overheat switch.
Is the action complete?
ÐVerify repairÐ
371. Remove the A/C compressor relay.
2. Idle the engine.
Is the compressor clutch still engaged when A/C is not
selected?
ÐGo to Step 38Go to Step 39
38Repair the short to voltage between the A/C clutch and
A/C compressor relay.
Is the action complete?
ÐVerify repairÐ
391. Reinstall the A/C compressor relay.
2. Remove the A/C thermostat relay.
3. Engine idling.
Is the compressor clutch still engaged when A/C is not
selected?
ÐGo to Step 40Go to Step 42
40Use a DVM to check for a short to ground between the
A/C compressor relay and F4 of the PCM.
Was a short detected?
ÐGo to Step 41Go to Step 25
41Repair the short to ground between the PCM and A/C
compressor relay.
Is the action complete?
ÐVerify repairÐ
42Repair the short to ground between the A/C thermostat
relay and the electronic thermostat.
Is the action complete?
ÐVerify repairÐ