2004 ISUZU TF SERIES engine

6E-140 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
P1508 B Idle Air Control System
Low/Closed 1. No DTC relating to MAF sensor, IAT sensor,
ECT sensor, TPS, CMP sensor, CKP sensor,
VSS and system voltage.
2. Engine speed is between 675rpm and
6000rpm.
3. Engine coolant temperature is more than
75
C.
4. Intake air temperature is between -10
C and
80
C.
5. Vehicle is stopping.
6. Small amount of intake air through the idle air
control valve. (Idle air control valve is sticking
at close position.) Above conditions are met
for 2 seconds. 1. IAC valve harness open circuit, short to
ground circuit or short to voltage circuit.
2. Poor connector connection.
3. IAC valve malfunction.
4. IAC valve is sticking at close position.
5. ECM malfunction. B13/
B14/
B16/
B17 -
22
P1509 B Idle Air Control System
High/Open 1. No DTC relating to MAF sensor, IAT sensor,
ECT sensor, TPS, CMP sensor, CKP sensor,
VSS and system voltage.
2. Engine speed is between 675rpm and
6000rpm.
3. Engine coolant temperature more than 75
C.
4. Intake air temperature is between -10
C and
80
C.
5. Vehicle is stopping.
6. Large amount of intake air through the idle air
control valve. (Idle air control valve is sticking
at open position.) Above conditions are met
for 2 seconds. Fuel cut is operated at high idle
speed.
Correct amount of air intake
through the idle air control
valve. (Correct movement of
the idle air control valve.)

1. IAC valve harness open circuit, short to
ground circuit or short to voltage circuit.
2. Poor connector connection.
3. IAC valve malfunction.
4. IAC valve is sticking at open position.
5. ECM malfunction. B13/
B14/
B16/
B17 - 65 P1601 D CAN BUS Off CAN BUS off condition is detected consecutively.
CAN BUS on condition is
detected consecutively for 2
seconds. 1. ECM and TCM communication circuit open,
short to ground or short to voltage.
2. Electrical interference.
3. ECM malfunction.
4. TCM malfunction. A10/
A11 - 67 U2104 D CAN BUS Reset Counter
Overrun 1. No DTC CAN BUS Off.
2. CAN valid counter does not change for 2
seconds. Torque reduction control is
disable.
CAN valid counter changes
consecutively for 2 seconds. 1. ECM and TCM communication circuit open,
short to ground or short to voltage.
2. Electrical interference.
3. ECM malfunction.
4. TCM malfunction. A10/
A11 P1767/
U2104 (AT)

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-141
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
P1626 - Immobilizer No Signal No response from immobilizer control unit.
1. ECM and immobilizer control unit
communication circuit open circuit, short to
ground circuit or short to voltage circuit.
2. Electrical interference.
3. Magnetic interference.
4. ECM malfunction.
5. Immobilizer control unit malfunction.
6. Transponder key malfunction. B18/
B32 B**** P1631 - Immobilizer Wrong Signal Received response is not correct.
1. ECM malfunction.
2. Immobilizer control unit malfunction.
3. Transponder key malfunction. - B**** P1648 - Wrong Security Code Entered Received incorrect security code.
1. ECM malfunction.
2. Immobilizer control unit malfunction.
3. Transponder key malfunction. - B****
67
P1649 - Immobilizer Function Not
Programmed Immobilizer function is not programmed in the
ECM. 1. Engine does not start.
2. Check engine lamp flash.
No recovery
ECM malfunction. - B****

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

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

6E-144 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Too low fuel pressure (poor fuel) will cause one or more of following DTCs to be set.





P0131 (Flash Code 15): O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)





P0151 (Flash Code 15): O2 Sensor Circuit Low Voltage (Bank 2 Sensor 1)





P0171 (Flash Code 44): O2 Sensor System Too Lean (Bank 1)





P0174 (Flash Code 44): O2 Sensor System Too Lean (Bank 2)





P1171 (Flash Code 44): Fuel Supply System Lean During Power Enrichment (Bank 1)





P1172 (Flash Code 44): Fuel Supply System Lean During Power Enrichment (Bank 2)

Too high fuel pressure (excessive fuel) will cause one or more of following DTCs to be set.





P0132 (Flash Code 15): O2 Sensor Circuit High Voltage (Bank1 Sensor 1)





P0152 (Flash Code 15): O2 Sensor Circuit High Voltage (Bank 2 Sensor 1)





P0172 (Flash Code 45): O2 Sensor System Too Rich (Bank 1)





P0175 (Flash Code 45): O2 Sensor System Too Rich (Bank 2)




RTW36ELF000101

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 -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.

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

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-147
Step Action Value (s) Yes No
4
1. Using the Tech 2, ignition "On" and engine "On".
2. Monitor the "Mass Air Flow" in the data display.
Does the Tech 2 indicate correct "Mass Air Flow" as
shown in the following graph, when engine speed is
increasing little by little?
Characteris tic of MAF Sens or -Ref erence (No Engine Load)-
0 5 10 15 20 25 30 35 40 45 50
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
Eng i ne Speed ( r pm) ( T ech2 R eadi ng )
Mass Air Flow (g/s)
( T ec h2 R eadi ng)
- Go to Step 6 Go to Step 5
5
Remove the MAF & IAT sensor assembly and check
for the following conditions.

Objects blocking the air cleaner.

Objects blocking the MAF sensor.

Objects blocking the throttle valve.

Vacuum leaking at intake duct.

Vacuum leaking at throttle body.
If a problem is found, repair as necessary.
Was the problem found?
- Verify repair Go to Step 6
6
Check for poor/faulty connection at the MAF sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?


 E-61(B)
E-63






- Verify repair Go to Step 7
7
Remove the MAF & IAT sensor assembly and visually
check.
Was the problem found?
- Go to Step 11 Go to Step 8