ISUZU TF SERIES 2004 Workshop Manual

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-125
Step Action Value (s) Yes No
12
 Using the DVM and check the A/C compressor relay
ground circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the ECM connector.
3. Remove the A/C compressor relay from the relay
box.
4. Check the circuit for open or short to ground circuit.
Was the problem found?
E-61(B)
X-14









- Repair faulty
harness and
verify repair Go to Step 13
13
Using the DVM and check the A/C magnet clutch
power supply circuit.
1. Using the Tech 2, ignition "On" and engine "Off".
2. Select the "Miscellaneous Test" and perform the
"A/C Clutch Relay" in the "Relays".
3. Operate the Tech 2 in accordance with procedure.
4. Disconnect the A/C clutch connector. Check the
circuit for open or short to ground circuit.
Was the DVM indicated specified value?
E-2
V



10 – 14.5V Go to Step 27 Go to Step 14
14
Repair the open or short to ground circuit between the
A/C compressor relay and A/C magnet clutch.
Is the action complete?
E-2X-14






- Verify repair -

6E-126 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
15
Check for poor/faulty connection at the thermo relay,
triple pressure switch, thermostat or ECM connector. If
a poor/faulty connection is found, repair as necessary.
Was the problem found?
E-61(B)
X-15







C-24C-55









- Verify repair Go to Step 16
16
 Using the DVM and check the thermo relay.
1. Ignition "Off", engine "Off".
2. Remove the thermo relay from the relay box.
3. Check the relay coil.
Was the DVM indicated specified value?
X-15






Approximately
140

Go to Step 17 Replace thermo
relay and verify
repair
17
 Using the DVM and check the thermo relay power
supply circuit.
1. Ignition "On", engine "Off".
2. Remove the thermo relay from the relay box.
3. Check the circuit for open or short to ground circuit.
Was the DVM indicated specified value?
X-15





VV

10 – 14.5V Go to Step 19 Go to Step 18
18
Repair the open or short to ground circuit between the
"A/C" fuse (10A) and thermo relay.
Is the action complete?
- Verify repair -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-127
Step Action Value (s) Yes No
19
Using the DVM and check the triple pressure switch
circuit.
1. Ignition "On", engine "Off".
2. Turn "On" blower motor.
3. Disconnect the triple pressure switch connector.
4. Check the circuit for open or short to ground circuit.
Was the DVM indicated specified value?
C-24
V



10 – 14.5V Go to Step 21 Go to Step 20
20
Repair the open or short to ground circuit between the
thermo relay and triple pressure switch.
Is the action complete?
C-24
X-15





- Verify repair -
21
Using the DVM and check the triple pressure switch.
1. Ignition "Off", engine "Off".
2. Disconnect the triple pressure switch connector.
3. Check the switch.
Was the switch closed?
Triple Pressure
SW






- Go to Step 23 Go to Step 22
22
Replace the triple pressure switch.
Is the action complete?
- Verify repair -

6E-128 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
23
Using the DVM and check the thermostat circuit.
1. Ignition "On", engine "Off".
2. Turn "On" blower motor.
3. Disconnect the triple pressure switch connector.
4. Check the circuit for open or short to ground circuit.
Was the DVM indicated specified value?
C-55
V



10 – 14.5V Go to Step 25 Go to Step 24
24
Repair the open or short to ground circuit between the
triple pressure switch and thermostat.
Is the action complete?
C-55C-24



- Verify repair -
25
Replace the thermostat.
Is the action complete?
- Verify repair -
26
Using the DVM and check the thermo relay input
circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the ECM connector.
3. Remove the thermo relay from the relay box.
4. Check the circuit for open or short to ground circuit.
Was the problem found?
E-61(B)
X-15










- Repair faulty
harness and
verify repair Go to Step 28
27
Replace the A/C compressor.
Was the problem solved?
- Verify repair -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-129
Step Action Value (s) Yes No
28
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved?
- Verify repair Go to Step 29
29
Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual. Following
ECM programming, the immobilizer system (if
equipped) must be linked to the ECM. Refer to section
11 “Immobilizer System-ECM replacement” for the
ECM/Immobilizer linking procedure.
- Verify repair -

6E-130 3.5L ENGINE DRIVEABILITY AND EMISSIONS
ECM DIAGNOSTIC TROUBLE CODES (DTC)

DTC Type A

Emission related.

Requests illumination of the MIL (Malfunction Indicator Lamp = Check Engine Lamp) of the first trip with a fail.

Stores a history DTC on the first trip with a fail.

Stores a freeze frame (If empty).

Stores a fail record.

Updates the fail record each time the diagnostic test fails.

DTC Type B

Emission related.

"Armed" after one trip with fail.

"Disarmed" after one trip with a pass.

Requests illumination of the MIL on the second consecutive trip with a fail.

Store a history DTC on the second consecutive trip with a fail. (The DTC will be armed after the first fail.)

Stores a freeze frame on the second consecutive trip with a fail (If empty).

Stores a fail record when the first test fails (not dependent on consecutive trip).

Updates the fail record each time the diagnostic test fails.

DTC Type D

Non emission related.

Does not request illumination of any lamp.

Stores a history DTC on the first trip with a fail.

Does not store a freeze frame.

Stores fail record when test fails.

Updates the fail record each time the diagnostic test fails.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-131

Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0101 B Mass Air Flow Sensor Circuit
Range/Performance 1. No DTC relating to barometer sensor, TPS,
CMP sensor, CKP sensor and MAF sensor
(low input & high input).
2. Engine speed is between 2800rpm and
4500rpm.
3. Throttle position sensor output voltage is
between 1V and 3V.
4. Intake air temperature is between -14
C and
70
C.
5. Air flow amount below 0.04g/s (small air) or
more than 177g/s (large air). Above
conditions are met for 3 seconds. No fail-safe function. Air flow amount is more than
0.04g/s or below 177g/s. 1. Air intake is obstructed.
2. Sensor signal circuit short to voltage circuit.
3. MAF sensor malfunction.
4. Electrical interference.
5. ECM malfunction. B20/
B39 - P0102 A Mass Air Flow Sensor Circuit
Low Input MAF sensor output voltage is below 0.3V. MAF sensor output voltage is
more than 0.3V. 1. Sensor power supply circuit open circuit.
2. Sensor signal circuit open or short to ground
circuit.
3. Poor connector connection.
4. MAF sensor malfunction.
5. ECM malfunction. B20 -
61
P0103 A Mass Air Flow Sensor Circuit
High Input MAF sensor output voltage is more than 4.9V. The ECM uses default mass
air flow value based on IAC
valve position, throttle position,
barometer pressure and
engine speed.
MAF sensor output voltage is
below 4.9V. 1. Sensor signal circuit short to voltage circuit.
2. Sensor ground circuit open or short to voltage
circuit.
3. MAF sensor malfunction.
4. ECM malfunction. B20/
B39 P0113/
P0123/
P0341/
P0342
P0112 A Intake Air Temperature Sensor
Low Input IAT sensor output voltage is below 0.08V. IAT sensor output voltage is
more than 0.08V. 1. Sensor signal circuit short to ground circuit.
2. IAT sensor malfunction.
3. ECM malfunction. A19 -
23

P0113 A Intake Air Temperature Sensor
High Input IAT sensor output voltage is more than 4.9V. The ECM use 40
C conditions
as substitute.
IAT sensor output voltage is
below 4.9V. 1. Sensor signal circuit open or short to voltage
circuit.
2. Sensor ground circuit open or short to voltage
circuit.
3. Poor connector connection
4. IAT sensor malfunction.
5. ECM malfunction. A19/
B39 P0103/
P0123/
P0341/
P0342

6E-132 3.5L ENGINE DRIVEABILITY AND EMISSIONS Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0117 A Engine Coolant Temperature
Sensor Low Input ECT sensor output voltage is below 0.08V. ECT sensor output voltage is
more than 0.08V. 1. Sensor signal circuit short to ground circuit.
2. ECT sensor malfunction.
3. ECM malfunction. A21 -
14
P0118 A Engine Coolant Temperature
Sensor High Input ECT sensor output voltage is more than 4.8V. The ECM uses default engine
coolant temperature value
based on start-up ECT and
time from start.
ECT sensor output voltage is
below 4.8V. 1. Sensor signal circuit open or short to voltage
circuit.
2. Sensor ground circuit open or short to voltage
circuit.
3. Poor connector connection
4. ECT sensor malfunction.
5. ECM malfunction. A21/
A22 P0406
1. No DTC relating to barometer sensor, ECT
sensor, CMP sensor, CKP sensor, MAF
sensor and TPS (low input & high input).
2. Engine speed is more than 2000rpm.
3. Engine coolant temperature is more than
75
C.
4. TPS output voltage is between 0.24V and
0.26V. Above conditions are met for 3
seconds.
OR
P0121 A Throttle Position Sensor
Range/Performance
1. No DTC relating to barometer sensor, ECT
sensor, CMP sensor, CKP sensor, MAF
sensor and TPS (low input & high input).
2. Engine speed is below 3200rpm.
3. Engine coolant temperature is more than
75
C.
4. TPS output voltage is between 4.54V and
4.56V. Above conditions are met for 3
seconds. No fail-safe function. TPS output voltage is below
0.24V or more than 0.26V.
OR
TPS output voltage is below
4.54V or more than 4.56V. 1. TPS malfunction.
2. Sensor signal circuit short to voltage circuit.
3. Electrical interference.
4. ECM malfunction. B27/
B26/
B39 - P0122 A Throttle Position Sensor Low
Input TPS output voltage is below 0.24V. TPS output voltage is more
than 0.24V. 1. Sensor power supply circuit open or short to
ground circuit.
2. Sensor signal circuit open or short to ground
circuit.
3. Poor connector connection.
4. TPS malfunction.
5. ECM malfunction. B27/
B26 P0336/
P0337
or
P0342
21
P0123 A Throttle Position Sensor High
Input TPS output voltage is more than 4.56V. The ECM uses default throttle
position value based on mass
air flow and engine speed.
TPS output voltage is below
4.56V. 1. Sensor power supply circuit short to voltage
circuit.
2. Sensor signal circuit short to voltage circuit.
3. Sensor ground circuit open or short to voltage
circuit.
4. Poor connector connection.
5. TPS malfunction.
6. ECM malfunction. B27/
B26/
B39 P0103/
P0113/
P0341/
P0342

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-133
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0131 A O2 Sensor Circuit Low Voltage
(Bank 1 Sensor 1) B21/
B22 P0171/
P1171/
P1172 P0151 A O2 Sensor Circuit Low Voltage
(Bank 2 Sensor 1) 1. No DTC relating to ECT sensor, CMP sensor,
CKP sensor, VSS, injector control circuit,
ignition control circuit and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is between 1000rpm and
4000rpm.
3. Engine coolant temperature is between 70
C
and 110
C.
4. Vehicle speed is between 0km/h and
120km/h.
5. Engine load is between 80% and 160%.
6. Throttle position fluctuation is below 0.28V.
7. O2 sensor bank 1 or bank 2 output voltage is
more than 400mV for 50 seconds. "Open Loop" fuel control. O2 sensor bank 1 or bank 2
output voltage is below 400mV
for 50 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. ECM malfunction.
B23/
B24 P0174/
P1171/
P1172 P0132 A O2 Sensor Circuit High Voltage
(Bank 1 Sensor 1) B21/
B22 P0172 P0152 A O2 Sensor Circuit High Voltage
(Bank 2 Sensor 1) 1. No DTC relating to ECT sensor, CMP sensor,
CKP sensor, VSS, injector control circuit,
ignition control circuit and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is between 1000rpm and
4000rpm.
3. Engine coolant temperature is between 70
C
and 110
C.
4. Vehicle speed is between 0km/h and
120km/h.
5. Engine load is between 80% and 160%.
6. Throttle position fluctuation is below 0.28V.
7. O2 sensor bank 1 or bank 2 output voltage is
below 600mV for 50 seconds. "Open Loop" fuel control. O2 sensor bank 1 or bank 2
output voltage is more than
600mV for 50 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. AC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. EVAP purge solenoid valve malfunction.
9. Ignition system malfunction.
10. Spark plug malfunction.
11. ECM malfunction. B23/
B24 P0175 P0134 A O2 Sensor Circuit No Activity
Detected (Bank 1 Sensor 1) B21/
B22 -
15

P0154 A O2 Sensor Circuit No Activity
Detected (Bank 2 Sensor 1) 1.No DTC relating to MAF sensor, ECT sensor,
CMP sensor, CKP sensor, VSS, injector
control circuit and ignition control circuit.
2. Engine coolant temperature is more than
70
C.
3. Vehicle speed is more than 60km/h.
4. O2 sensor bank 1 or bank 2 output voltage is
between 350mV and 600mV. "Open Loop" fuel control. O2 sensor bank 1 or bank 2
output voltage is below 0.35mV
consecutively.
OR
O2 sensor bank 1 or bank 2
output voltage is more than
600mV consecutively. 1. O2 sensor malfunction.
2. ECM malfunction.
B23/
B24 -

6E-134 3.5L ENGINE DRIVEABILITY AND EMISSIONS Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure Parts Related
ECM Pin
No. Related
Multiple
DTC
P0171 B O2 Sensor System Too Lean
(Bank 1) - -
44
P0174 B O2 Sensor System Too Lean
(Bank 2) 1. No DTC relating to MAF sensor, IAT sensor,
ECT sensor, TPS, CMP sensor, CKP sensor,
VSS, injector control circuit, ignition control
circuit, O2 sensor circuit low voltage & high
voltage (bank 1 & 2) and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is more than 600rpm.
3. Intake air temperature is more than 50
C.
4. Engine coolant temperature is between 35
C
and 120
C.
5. Engine load is more than 20.
6. EVAP purge solenoid valve on-duty is below
100%.
7. Air-fuel ratio correction volume is more than
150% for 20 seconds. No fail-safe function. Air fuel ratio correction volume
is between 50% and 150% for
5 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. ECM malfunction.
- -
P0172 B O2 Sensor System Too Rich
(Bank 1) - -
45
P0175 B O2 Sensor System Too Rich
(Bank 2) 1. No DTC relating to MAF sensor, IAT sensor,
ECT sensor, TPS, CMP sensor, CKP sensor,
VSS, injector control circuit, ignition control
circuit, O2 sensor circuit low voltage & high
voltage (bank 1 & 2) and O2 sensor circuit no
activity (bank 1 & 2).
2. Engine speed is more than 600rpm.
3. Intake air temperature is more than 50
C.
4. Engine coolant temperature is between 35
C
and 120
C.
5. Engine load is more than 20.
6. EVAP purge solenoid valve on-duty is below
100%.
7. Air-fuel ratio correction volume is below 50%
for 20 seconds. No fail-safe function. Air fuel ratio correction volume
is between 50% and 150% for
5 seconds. 1. Sensor harness open or short to ground
circuit.
2. O2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. AC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. EVAP purge solenoid valve malfunction.
9. Ignition system malfunction.
10. Spark plug malfunction.
11. ECM malfunction. - -