2004 ISUZU TF SERIES ECU

11B – 56 ANTITHEFT SYSTEM
DTC 43 Driver Door Lock Switch Super lock Defect
Step Action Value (s) Yes No
1
2
3
4
5
6
7Was the Antitheft System Check"
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the Tech-2.
Is DTC 43 stored?
Check the driver door lock function.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “OFF”.
4. Observe to display door lock switch data with
the Tech-2.
5. Turn ON by driver door lock.
Does the Tech-2 display Closed?
1. Key position is “OFF”.
2. Observe to display door lock data with the
Tech-2.
3. Turn OFF by driver door lock.
Does the Tech-2 display Open?
1. Check the driver door lock switch circuit for
an open, short to ground, or short to voltage.
Also, check the door lock connector for
damage.
2. If a problem found, repair as necessary.
Was the problem found?
1. Repair or replace the driver door lock switch.
2. Check the DTC on the Tech-2.
Is DTC 43 stored?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the Tech-2.
Was the action complete?—
—
—
—
—
—
—Go to Step 2
Go to Step 3
Go to Step 4
Refer to
Diagnostic Aids,
and then go to
step 5
Verify repair
Go to Step 7
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
Go to Step 5
Go to Step 5
Go to Step 6
Verify repair
—

ANTITHEFT SYSTEM 11B – 57
DTC 44 Passenger Door Lock Switch lock Defect
Step Action Value (s) Yes No
1
2
3
4
5
6
7Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the Tech-2.
Is DTC 44 stored?
Check the passenger door lock function.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “OFF”.
4. Observe to display door lock switch data with
the Tech-2.
5. Turn ON by passenger door lock.
Does the Tech-2 display Closed?
1. Key position is “OFF”.
2. Observe to display door lock data with the
Tech-2.
3. Turn OFF by passenger door lock.
Does the Tech-2 display Open ?
1. Check the passenger door lock switch circuit
for an open, short to ground, or short to
voltage.
Also, check the door lock connector for
damage.
2. If a problem found, repair as necessary.
Was the problem found?
1. Repair or replace the passenger door lock
switch.
2. Check the DTC on the Tech-2.
Is DTC 44 stored?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the Tech-2.
Was the action complete?—
—
—
—
—
—
—Go to Step 2
Go to Step 3
Go to Step 4
Refer to
Diagnostic Aids,
and then go to
step 5
Verify repair
Go to Step 7
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
Go to Step 5
Go to Step 5
Go to Step 6
Verify repair
—

11B – 58 ANTITHEFT SYSTEM
DTC 45 Passenger Door Lock Switch Unlock Defect
Step Action Value (s) Yes No
1
2
3
4
5
6
7Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the Tech-2.
Is DTC 44 stored?
Check the passenger door lock function.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “OFF”.
4. Observe to display door lock switch data with
the Tech-2.
5. Turn ON by passenger door lock.
Does the Tech-2 display Closed ?
1. Key position is “OFF”.
2. Observe to display door lock data with the
Tech-2.
3. Turn OFF by passenger door lock.
Does the Tech-2 display Open ?
1. Check the passenger door lock switch circuit
for an open, short to ground, or short to
voltage.
Also, check the door lock connector for
damage.
2. If a problem found, repair as necessary.
Was the problem found?
1. Repair or replace the passenger door lock
switch.
2. Check the DTC on the Tech-2.
Is DTC 45 stored?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the Tech-2.
Was the action complete?—
—
—
—
—
—
—Go to Step 2
Go to Step 3
Go to Step 4
Refer to
Diagnostic Aids,
and then go to
step 5
Verify repair
Go to Step 7
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
Go to Step 5
Go to Step 5
Go to Step 6
Verify repair
—

ANTITHEFT SYSTEM 11B – 59
DTC 47 Battery Voltage For Door Lock Actuators Is Missing
Step Action Value (s) Yes No
1
2
3
4
5
6
7Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the Tech-2.
Is DTC 47 stored?
Check the antilock system voltage.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Observe to display system voltage data with
the Tech-2.
Is the voltage near the specified value ?
1. Key position is “OFF”.
2. Check the battery voltage.
3. If a problem found, repair as necessary.
(Chage battery)
Was the problem found?
Check the door lock motor output voltage.
1. Key position is “OFF”.
2. Connect a digital volt meter to measure
voltage.
between ACU terminal 7 and body ground.
3. Key position is “ON”.
4. Observe to display voltage with the DVM.
5. Door lock ON.
Is the voltage near the specified value ?
1. Check the door lock motor circuit for an open,
short to ground, or short to voltage.
Also, check the door lock motor connector for
damage.
2. If a problem found, repair as necessary.
Was the problem found?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the Tech-2.
Was the action complete?—
—
12V
—
12V
—
—Go to Step 2
Go to Step 3
Go to Step 5
Verify repair
Go to Step 6
Verify repair
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
Go to Step 4
Refer to
Diagnostic Aids
Go to Step 7
—
—

11B – 60 ANTITHEFT SYSTEM
DTC 50 A/D Converter Defect Or Battery Voltage Less Than 9 Volt
Step Action Value (s) Yes No
1
2
3
4
5
6Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the Tech-2.
Is DTC 50 stored?
Check the antilock system voltage.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Observe to display system voltage data with
the Tech-2.
Is the voltage near the specified value ?
1. Key position is “OFF”.
2. Check the battery voltage.
3. If a problem found, repair as necessary.
(Chage battery)
Was the problem found?
1. Check the ignition feed circuit for an open,
short to ground.
Also, check the ACU ground circuit for
damage.
2. If a problem found, repair as necessary.
Was the problem found?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the Tech-2.
Was the action complete?—
—
12V
—
—
—Go to Step 2
Go to Step 3
Go to Step 7
Verify repair
Verify repair
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
Go to Step 4
Go to Step 5
Refer to
Diagnostic Aids
—

ANTITHEFT SYSTEM 11B – 61
DTC 51 E E P R OM Defect
Step Action Value (s) Yes No
1
2
3Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the Tech-2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the Tech-2.
Is DTC 51 stored?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the Tech-2.
Was the action complete?—
—
—Go to Step 2
Go to Step 3
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
—

ANTITHEFT SYSTEM 11B – 63
DTC 55 Control unit defect
Step Action Value (s) Yes No
1
2
3Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF” and keep the position
for more than 30 seconds.
2. Key position is “ON”.
3. Check the DTC on scan tool.
Is DTC 55 stored?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the tech2.
Was the action complete?—
—
—Go to Step 2
Go to Step 3
Verify repairGo to antitheft
System Check
Verify repair
—

11B – 64 ANTITHEFT SYSTEM
DTC 123 Output flasher short circit to ground or broken wire
Step Action Value (s) Yes No
1
2
3
4
5Was the Antitheft System Check
performed?
Recheck the DTC.
1. Key position is “OFF”.
2. Install the tech2 on vehicle.
3. Key position is “ON”.
4. Check the DTC on the tech2.
Is DTC 123 stored?
1. Check the flasher circuit for an open, short to
ground, or short to voltage.
Also, check the flasher connector for damage.
2. If a problem found, repair as necessary.
Was the problem found?
Check the flasher function.
1. Key position is “OFF”.
2. Connect a jamper wire between ACU terminal
28 and body ground.
3. Key position is “ON”.
4. Observe to operate flasher lamp.
If the problem found about the flasher lamp
circuit, repair as necessary.
Was the problem found?
Replace the antitheft control unit (ACU).
IMPORTANT:The replacement ACU must be
programmed the security data by the tech2.
Was the action complete?—
—
—
—
—Go to Step 2
Go to Step 3
Verify repair
Verify repair
Verify repairGo to antitheft
System Check
Refer to
Diagnostic Aids
Go to Step 4
Go to Step 5
—