check engine ISUZU TF SERIES 2004 Workshop Manual

6E –210 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor As Stored By ECU ” in
“ F0: Diagnostic Trouble Codes ”.
Is the DTC P0335 (Symptom Code B) or P0335
(Symptom Code D) stored as “Present Failure ”? —Go to Step 3 Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech 2, ignition “On ” and engine “Off ”.
2. Select “F1: Clear DTC Information ” in “F0:
Diagnostic Trouble Codes ” with the Tech 2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0335 (Symptom Code B) or P0335
(Symptom Code D) stored in this ignition cycle? —Go to Step 4 Refer to
Diagnostic Aids and Go to Step
4
4 Check for poor/faulty connection at the CKP sensor or ECM connector. If a poor/faulty connection is found,
repair the faulty terminal.
Was the problem found?
— Verify repair Go to Step 5
5 Visually check the CKP sensor. If a faulty installation is found, repair as necessary.
Was the problem found? —Verify repair Go to Step 6
6 Using the DVM and check the CKP sensor circuit. Breaker box is available:
1. Ignition “Off ”, engine “Off ”.
2. Install the breaker box as type A. (ECM disconnected) Ref. Page 6E-103
3. Check the resistance of the CKP sensor.
Was the DVM indicated specified value?
Breaker box is not available:
1. Ignition “Off ”, engine “Off ”.
2. Disconnect the ECM connector.
3. Check the resistance of the CKP sensor.
Was the DVM indicated specified value?
Approx imately 0.9k
at 20 °CGo to Step 10 Go to Step 7
Step Action Value(s) Yes No
101
90 9823
1 E-9
C-57(B)
9098


Breaker Box
90
98
C-57(B)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –211
7 Using the DVM and check the CKP sensor circuit.
1. Ignition “Off ”, engine “Off ”.
2. Disconnect the CKP sensor connector.
3. Check the resistance of the CKP sensor.
Was the DVM indicated specified value?
Approx imately 0.9k
at 20 °CGo to Step 8Go to Step 14
8 Using the DVM and check the CKP sensor circuit. Breaker box is available:
1. Ignition “Off ”, engine “Off ”.
2. Install the breaker box as type A. (ECM disconnected) Ref. Page 6E-103
3. Disconnect the CKP sensor connector.
4. Check the circuit for open, short to sensor wire or short to ground circuit.
Was the problem found?
Breaker box is not available: 1. Ignition “Off ”, engine “Off ”.
2. Disconnect the ECM connector.
3. Disconnect the CKP sensor connector.
4. Check the circuit for open, short to sensor wire or short to ground circuit.
Was the problem found?
— Repair faulty
harness and verify repair Go to Step 9
Step Action Value(s) Yes No
1
2
E-9
9098
Breaker Box101




9098
Breake r BoxE-9



6E –212 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
9 Using the DVM and check the CKP sensor circuit.
1. Ignition “On ”, engine “Off ”.
2. Disconnect the CKP sensor connector.
3. Check the circuit for short to power supply circuit.
If the DVM indicated out of specified value, repair
faulty harness and verify repair.
Is the action complete?
Less than 1V Verify repair —
10 Using the DVM and check the CKP sensor signal. 1. Ignition “On ”, engine “On ”.
2. Measure the CKP output voltage at the sensor and ECM.
Does the tester indicate standard voltage?
If a oscilloscope is available, monitor the CKP sensor
signal. Does the oscilloscope indicate correct wave
form?
Go to Step 13 Go to Step 11
11 Remove the CKP sensor from the flywheel housing and visually check.
Check for the following conditions.
 Objects sticking the CKP sensor.
 Objects sticking the CKP sensor pulser.
If a problem is found, repair as necessary.
Was the problem found? —Verify repair Go to Step 12
12 Check the CKP sensor shield wire for open or short circuit.
Was the problem found? — Repair faulty
harness and verify repair Go to Step 13
Step Action Value(s) Yes No
1
2
VV
E-9
Measurement Point Voltage (V) (AC Range)
At CKP se nso r te rminal 2 & 1 Appro ximate ly 1.1 V a t 2000rpm
At ECM C57 co nnecto r 90 & 98
Cra nksha ft Po sitio n (CKP) Sensor Refe rence Wav e Form
0V 
Mea sure me nt Terminal: 90(+) 98(-)
Measurement Scale: 20V/div 2ms/div
Mea sure me nt Co ndition: Approx imately 2000rpm

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–213
13 Check any accessory parts which may cause electric
interference or magnetic interference.
Was the problem found?—Remove the
accessory parts
and verify repair Go to Step 14
14 Substitute a known good CKP sensor and recheck.
Was the problem solved?—Go to Step 15Go to Step 16
15 Replace the CKP sensor.
Was the problem solved?—Verify repair Go to Step 16
16 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 repairGo to Step 17
17 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— Step Action Value(s) Yes No

6E –214 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0335 (Symptom Code E) (Flash Code 43)
Engine Speed Input Circuit Range/Performance
Step Action Value(s) Yes No
1Was 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 As Stored By ECU ” in
“ F0: Diagnostic Trouble Codes ”.
Is the DTC P0335 (Symptom Code E) stored as
“ Present Failure ”? —Go to Step 3 Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech 2, ignition “On ” and engine “Off ”.
2. Select “F1: Clear DTC Information ” in “F0:
Diagnostic Trouble Codes ” with the Tech 2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0335 (Symptom Code E) stored in this
ignition cycle? —Go to Step 4 Refer to
Diagnostic Aids and Go to Step
4
4 Ask to the customer whether over-speed condition such as miss-gear shifting etc. has been experienced
or not. — Ex plain the
reason of DTC
to the customer Go to Step 5
5 Check for poor/faulty connection at the CKP sensor or ECM connector. If a poor/faulty connection is found,
repair the faulty terminal.
Was the problem found?
— Verify repair Go to Step 6
101
90 9823
1 E-9
C-57(B)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–215
6 Using the DVM and check the CKP sensor signal.
1. Ignition “On”, engine “On”.
2. Measure the CKP output voltage at the sensor
and ECM.
Does the tester indicate standard voltage?
If a oscilloscope is available, monitor the CKP sensor
signal. Does the oscilloscope indicate correct wave
form?
Go to Step 9Go to Step 7
7 Remove the CKP sensor from the flywheel housing
and visually check.
Check for the following conditions.
Objects sticking the CKP sensor.
Objects sticking the CKP sensor pulser.
If a problem is found, repair as necessary.
Was the problem found? —Verify repair Go to Step 8
8 Check the CKP sensor shield wire for open or short
circuit.
Was the problem found?—Repair faulty
harness and
verify repair Go to Step 9
9 Check any accessory parts which may cause electric
interference or magnetic interference.
Was the problem found?—Remove the
accessory parts
and verify repair Go to Step 10
10 Substitute a known good CKP sensor and recheck.
Was the problem solved?—Go to Step 11Go to Step 12
11 Replace the CKP sensor.
Was the problem solved?—Verify repair Go to Step 12
12 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 13 Step Action Value(s) Yes No
Measurement Point Voltage (V) (AC Range)
At CKP se nso r te rminal 2 & 1 Appro ximate ly 1.1 V a t
2000rpm
At ECM C57 co nnecto r 90 & 98
Cra nksha ft Po sitio n (CKP) Sensor Refe rence Wav e Form
0V
Mea sure me nt Terminal: 90(+) 98(-)
Measurement Scale: 20V/div 2ms/div
Mea sure me nt Co ndition: Approx imately 2000rpm

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–217
DIAGNOSTIC TROUBLE CODE (DTC) P0380 (SYMPTOM CODE 4)
(FLASH CODE 66) GLOW RELAY CIRCUIT VOLTAGE LOW
DIAGNOSTIC TROUBLE CODE (DTC) P0380 (SYMPTOM CODE 8)
(FLASH CODE 66) GLOW RELAY CIRCUIT VOLTAGE HIGH
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The voltage on the coil of the relay glow plug is supplied
by the relay engine control module (ECM) main. The
ECM switches glow relay to operate glow plug depends
on the coolant temperature.
In the after glow phase the lamp is not illuminated but
the glow plugs remain active for a certain period
depending on engine coolant temperature.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
Check for the following conditions:
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
66 P0380 4 ON Glo w Re la y Circuit Volta ge
Lo wGlow relay circuit open or
sho rt to ground circuit.No fa il-sa fe fun ctio n.
8 ON Glo w Re la y Circuit Volta ge
HighGlo w re la y circuit short to vo lt-
age circuit.

6E –218 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
 Poor connection at ECM-Inspect harness connectors
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 be OK, observe
the DTC P0380 display on the Tech2 while moving
connectors and wiring harnesses. A change in the
display will indicate the location of the fault.
Diagnostic Trouble Code (DTC) P0380 (Symptom Code 4) (Flash Code 66) Glow Relay Circuit Voltage Low
Step Action Value(s) Yes No
1Was 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 As Stored By ECU ” in
“ F0: Diagnostic Trouble Codes ”.
Is the DTC P0380 (Symptom Code 4) stored as
“ Present Failure ”? —Go to Step 3 Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech 2, ignition “On ” and engine “Off ”.
2. Select “F1: Clear DTC Information ” in “F0:
Diagnostic Trouble Codes ” with the Tech 2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0380 (Symptom Code 4) stored in this
ignition cycle? —Go to Step 4 Refer to
Diagnostic Aids and Go to Step
4
4 Check for poor/faulty connection at the glow relay or ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
— Verify repair Go to Step 5
5 Using the DVM and check the glow relay. 1. Ignition “Off ”, engine “Off ”.
2. Remove the glow relay from the relay box .
3. Check the relay coil.
Was the DVM indicated specified value?
Approx imately 105
Go to Step 6 Replace glow
relay and verify repair
94
3
4
2
1
X-5
C-57
Grow Relay




4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –219
6 Using the DVM and check the glow relay power
supply circuit.
1. Ignition “On ”, engine “Off ”.
2. Remove the glow relay from the relay box .
3. Check the circuit for open or short to ground circuit.
Was the DVM indicated specified value?
10-14.5V Go to Step 8Go to Step 7
7 Repair the open or short to ground circuit between the ECM main relay and glow relay.
Is the action complete? —Verify repair —
8 Using the DVM and check the glow relay ground circuit.
Breaker box is available:
1. Ignition “Off ”, engine “Off ”.
2. Install the breaker box as type A. (ECM disconnected) Ref. Page 6E-103
3. Remove the glow relay from the relay box .
4. Check the circuit for open or short to ground circuit.
Was the problem found?
Breaker box is not available: 1. Ignition “Off ”, engine “Off ”.
2. Disconnect the ECM connector.
3. Remove the glow relay from the relay box .
4. Check the circuit for open or short to ground circuit.
Was the problem found?
— Repair faulty
harness and verify repair Go to Step 9
Step Action Value(s) Yes No
2
V
X-5
X- 594Breaker Box




3
94
X-5
C-57

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–221
Diagnostic Trouble Code (DTC) P0380 (Symptom Code 8) (Flash Code 66)
Glow Relay Circuit Voltage High
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go 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 As Stored By ECU” in
“F0: Diagnostic Trouble Codes”.
Is the DTC P0380 (Symptom Code 8) stored as
“Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech 2, ignition “On” and engine “Off”.
2. Select “F1: Clear DTC Information” in “F0:
Diagnostic Trouble Codes” with the Tech 2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU” in the “F0:
Diagnostic Trouble Codes”.
Was the DTC P0380 (Symptom Code 8) stored in this
ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
4 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 5
5 Substitute a known good ECM and recheck.
Was the problem solved?
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. —Go to Step 6—
6 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—