Throttle Position Sensor ISUZU TF SERIES 2004 Repair Manual
[x] Cancel search | Manufacturer: ISUZU, Model Year: 2004, Model line: TF SERIES, Model: ISUZU TF SERIES 2004Pages: 4264, PDF Size: 72.63 MB
Page 2077 of 4264

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-81
TYPICAL SCAN DATA & DEFINITIONS (O2 SENSOR DATA)
Use the typical values table only after the On-Board Diagnostic System check has been completed, no DTC(s) were noted, and you have determined that the On-Board
Diagnostic are functioning properly.
Tech2 values from a properly running engine may be used for comparison with the engine you are diagnosing.
Condition : Vehicle stopping, engine running, air conditioning off & after warm-up (Coolant temperature approximately 80 C)
Tech 2
Parameter
Units Idle 2000rpm Definitions
1 Ignition Voltage V 10.0 14.5 10.0 14.5 This displays the system voltage measured by the ECM at ignition feed.
2 Engine Speed rpm 710 860 1950 2050 The actual engine speed is measured by ECM from the CKP sensor 58X signal.
3 Desired Idle
Speed rpm 750 770 750 770 The desired engine idle speed that the ECM commanding.
The ECM compensates for various engine loads.
4 Engine Coolant
Temperature C or F 80 90 (C) 80 90 (C) The ECT is measured by ECM from ECT sensor output voltage.
When the engine is normally warm upped, this data displays approximately 80 °C or
more.
5 Start Up ECT
(Engine Coolant
Temperature) C or F Depends on ECT
at start-up
Depends on ECT
at start-up
Start-up ECT is measured by ECM from ECT sensor output voltage when engine is
started.
6 Throttle Position % 0 4 6 Throttle position operating angle is measured by the ECM from throttle position
output voltage.
This should display 0% at idle and 99 100% at full throttle.
7 Throttle Position
Sensor V 0.4 0.7 0.6 0.8 The TPS output voltage is displayed.
This data is changing by accelerator operating angle.
8 Mass Air Flow g/s 5.0 8.0 13.0 16.0 This displays intake air amount.
The mass air flow is measured by ECM from the MAF sensor output voltage.
9 Air Fuel Ratio 14.7:1 14.7:1 This displays the ECM commanded value. In closed loop, this should normally be
displayed around 14.2:1 14.7:1.
10 Engine Load % 2 7 8 15 This displays is calculated by the ECM form engine speed and MAF sensor reading.
Engine load should increase with an increase in engine speed or air flow amount.
11 B1 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
12 B2 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
When the engine is first started the system is in "Open Loop" operation.
In "Open Loop", the ECM ignores the signal from the oxygen sensors.
When various conditions (ECT, time from start, engine speed & oxygen sensor
output) are met, the system enters "Closed Loop" operation.
In "Closed Loop", the ECM calculates the air fuel ratio based on the signal from the
oxygen sensors.
13 B1S1 O2 Sensor
(Bank1 Sensor 1)
mV 50 950 50 950
14 B2S1 O2 Sensor
(Bank2 Sensor 1)
mV 50 950 50 950
This displays the exhaust oxygen sensor output voltage.
Should fluctuate constantly within a range between 10mV (lean exhaust) and
1000mV (rich exhaust) while operating in closed loop.
15 B1 O2 Sensor
Ready (Bank 1)
Yes/No Yes Yes
16 B2 O2 Sensor
Ready (Bank 2)
Yes/No Yes Yes
This displays the status of the exhaust oxygen sensor.
This display will indicate "Yes" when the ECM detects a fluctuating oxygen sensor
output voltage sufficient to allow closed loop operation.
This will not occur unless the oxygen sensor is warmed up.
17 B1 Long Term
Fuel Trim (Bank
1)
% -10 20 -10 20
18 B2 Long Term
Fuel Trim (Bank
2)
% -10 20 -10 20
The long term fuel trim is delivered from the short term fuel term values and
represents a long term correction of fuel delivery for bank in question.
A value of 0% indicates that fuel delivery requires no compensation to maintain the
ECM commanded air fuel ratio.
A negative value indicates that the fuel system is rich and fuel delivery is being
reduced (decreased injector pulse width).
A positive value indicates that a lean condition exists and the ECM is compensating
by add fuel (increased injector pulse width).
Because long term fuel trim tends to follow short term fuel trim, a value in the
negative range due to canister purge at idle should not be considered unusual.
Excessive long term fuel trim values may indicate an rich or lean condition.
Page 2127 of 4264

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 -14C and
70C.
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 40C 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
Page 2128 of 4264

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
75C.
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
75C.
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
Page 2129 of 4264

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 70C
and 110C.
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 70C
and 110C.
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
70C.
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 -
Page 2131 of 4264

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-135
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
P1171 D Fuel Supply System Lean
During Power Enrichment
(Bank 1) B21/
B22/
-
44
P1172 D Fuel Supply System Lean
During Power Enrichment
(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 between 1000rpm and
6000rpm.
3. Intake air temperature is below 70C.
4. Engine coolant temperature is between 30C
and 120C.
5. Engine load is between 150 and 255.
6. Throttle position output is more than 2.22V
and fluctuation is below 0.28V.
7. Except fuel cut operation.
8. O2 sensor output voltage below 250mV for 10
seconds. No fail-safe function.
O2 sensor output voltage is
more than 520mV 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.
B23/
B24 -
P0201 A Injector 1 Control Circuit
A36 - P0202 A Injector 2 Control Circuit
B3 - P0203 A Injector 3 Control Circuit
A35 - P0204 A Injector 4 Control Circuit
B4 - P0205 A Injector 5 Control Circuit
A34 -
31
P0206 A Injector 6 Control Circuit 1. No DTC relating to CMP sensor and CKP
sensor.
2. Under sequential injection.
3. Injection pulse is between 2.5ms and 7.5 ms.
4. Except fuel cut operation.
5. Engine speed is between 600rpm and
2000rpm.
6. 30 injection signals are not detected
consecutively. No fail-safe function. 30 injection signals are
detected consecutively. 1. Injector harness open circuit, short to ground
or short to voltage.
2. Injector malfunction.
3. ECM malfunction.
B5 -
Page 2138 of 4264

6E-142 3.5L ENGINE DRIVEABILITY AND EMISSIONS
MULTIPLE DTC SETS TROUBLESHOOTING AIDS
An open or short to voltage circuit in the sensor ground circuit between the ECM terminal A22 and splice will cause
one or more of following DTCs to be set:
P0406 (Flash Code 32): EGR Circuit High
P0118 (Flash Code 14): Engine Coolant Temperature Sensor High Input
A short to ground circuit in the sensor power supply circuit between the ECM terminal A24 and splice will cause one
or more of following DTCs to be set:
P0122 (Flash Code 21): Throttle Position Sensor Low Input
P0336 (Flash Code 29): Crankshaft Position Sensor Circuit Range/Performance (58X)
P0337 (Flash Code 29): Crankshaft Position Sensor Circuit No Signal (58X)
RTW46EMF000201
Page 2139 of 4264

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-143
An open or short to voltage circuit in the sensor ground circuit between the ECM terminal B39 and splice will cause
one or more of following DTCs to be set:
P0103 (Flash Code 61): Mass Air Flow Sensor Circuit High Input
P0113 (Flash Code 23): Intake Air Temperature Sensor High Input
P0123 (Flash Code 21): Throttle Position Sensor High Input
P0341(Flash Code 41): Camshaft Position Sensor Circuit Range/Performance
P0342 (Flash Code 41): Camshaft Position Sensor Circuit No Signal
An open circuit in the sensor power supply circuit between the ECM terminal B27 and splice will cause one or more of
following DTCs to be set:
P0122 (Flash Code 21): Throttle Position Sensor Low Input
P0342 (Flash Code 41): Camshaft Position Sensor Circuit No Signal
A short to ground circuit in the sensor power supply circuit between the ECM terminal B27 and splice will cause one
or more of following DTCs to be set:
P0122 (Flash Code 21): Throttle Position Sensor Low Input
P0336 (Flash Code 29): Crankshaft Position Sensor Circuit Range/Performance (58X)
P0337 (Flash Code 29): Crankshaft Position Sensor Circuit No Signal (58X)
A short to ground circuit in the sensor signal circuit between the ECM terminal B28 and sensor will cause one of
following DTC to be set:
P0337 (Flash Code 29): Crankshaft Position Sensor Circuit No Signal (58X)
RUW46EMF000101
Page 2141 of 4264

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-145
DIAGNOSTIC TROUBLE CODE (DTC) P0101 (FLASH CODE 61) MASS AIR
FLOW SENSOR CIRCUIT RANGE/PERFORMANCE
RUW46EMF000101
Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
61 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 -14C and 70C.
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.
Page 2142 of 4264

6E-146 3.5L ENGINE DRIVEABILITY AND EMISSIONS
CIRCUIT DESCRIPTION
The mass air flow (MAF) sensor measures the amount
of air which passes through it into the engine during a
given time. The Engine Control Module (ECM) uses the
mass air flow information to monitor engine operating
conditions for fuel delivery calculations. A large quantity
of air entering the engine indicates an acceleration o
r
high load situation, while a small quantity or air indicates
deceleration or idle.
The MAF sensor produces a frequency signal which
can be monitored using a Tech 2. The frequency will
vary within a range of around 4 to 7 g/s at idle to around
25 to 40 g/s at maximum engine load. DTC P0101 will
be set if the signal from the MAF sensor does not match
a predicted value based on throttle position and engine
RPM.
DIAGNOSTIC AIDS
An intermittent may be caused by the following:
Poor connections.
Mis-routed harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
Refer to Intermittents under service category
Symptoms.
Any un-metered air may cause this DTC to set. Check
for the following:
The duct work at the MAF sensor for leaks.
An engine vacuum leak.
The PCV system for vacuum leaks.
An incorrect PCV valve.
The engine oil dip stick not fully seated.
The engine oil fill cap loose or missing.
Diagnostic Trouble Code (DTC) P0101 (Flash Code 61)
Mass Air Flow Sensor Circuit Range/Performance
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go to On Board
Diagnostic (OBD)
System Check
2
1. Connect the Tech 2.
2. Review and record the failure information.
3. Select "F0: Read DTC Infor By Priority" in "F0:
Diagnostic Trouble Code".
Is the DTC P0101 stored as "Present Failure"?
- Go to Step 3 Refer to
Diagnostic Aids
and Go to Step 3
3
1. Using the Tech2, ignition "On" and engine "Off".
2. Select "Clear DTC Information" with the Tech2 and
clear the DTC information.
3. Operate the vehicle and monitor the "F5: Failed
This Ignition" in "F2: DTC Information"
Was the DTC P0101 stored in this ignition cycle?
- Go to Step 4 Refer to
Diagnostic Aids
and Go to Step 4
Page 2145 of 4264

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-149
DIAGNOSTIC TROUBLE CODE (DTC) P0102 (FLASH CODE 61) MASS AIR
FLOW SENSOR CIRCUIT LOW INPUT
RUW46EMF000101
Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
61 P0102 A Mass Air Flow Sensor
Circuit Low Input
MAF sensor output voltage is below 0.3V. The ECM uses default mass air flow
value based on IAC valve position,
throttle position, barometer pressure
and engine speed.