2004 ISUZU TF SERIES engine remove

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –257
7 Using the DVM and check the ECM main relay.
1. Ignition “Off ”, engine “Off ”.
2. Remove the ECM main relay from the relay box .
3. Check the relay coil.
Was the DVM indicated specified value?
120-150
Go to Step 8 Replace ECM
main relay and verify repair
8 Check for poor/faulty connection of the ECM ground at the body. If a poor/faulty connection is found, repair
as necessary.
Was the problem found?
— Verify repair Go to Step 9
9 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 10
10 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
ECM Main Relay


 




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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–269
Check for the following conditions:
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 P0645 display on the Tech2 while moving
connectors and wiring harnesses.
Diagnostic Trouble Code (DTC) P0645 (Sy mptom Code 4) (Flash Code 46) A/C
Compressor Relay Circuit Voltage Low
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 P0645 (Symptom Code 4) 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 P0645 (Symptom Code 4) stored in this
ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 Check for poor/faulty connection at the A/C
compressor 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 A/C compressor relay.
1. Ignition “Off”, engine “Off”.
2. Remove the A/C compressor relay from the relay
box .
3. Check the relay coil.
Was the DVM indicated specified value?
120-150
Go to Step 6Replace A/C
compressor
relay and verify
repair
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A/C Compressor Relay

 




6E–270 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
6 Using the DVM and check the A/C compressor relay
power supply circuit.
1. Ignition “On”, engine “Off”.
2. Remove the A/C compressor 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 A/C compressor relay.
Is the action complete?—Verify repair— Step Action Value(s) Yes No
3
V
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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–271
8 Using the DVM and check the A/C compressor relay
ground circuit.
Breaker box is available:
1. Ignition “Off”, engine “Off”.
2. Install the breaker box as type A. (ECM
disconnected)
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?
Breaker box is not available:
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?
—Repair faulty
harness and
verify repair Go to Step 9
9 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 10
10 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
X-14


41
Breaker Box


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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–275
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 P0703 (Symptom Code A) stored in this
ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 Check the “Stop Lamp fuse (15A)”.
If the fuse is burnt out, repair as necessary.
Was the problem found?—Verify repair Go to Step 5
5 Check for poor/faulty connection at the brake switch
or ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 6
6 Using the DVM and check the brake switch 1.
1. Ignition “Off”, engine “Off”.
2. Remove the brake switch connector at the brake
pedal.
3. Check the brake switch 1.
Was the DVM indicated specified value?
Pedal is not
stepped on:
Continuity
Pedal stepped
on: No
continuity Go to Step 7Replace pedal
switch and
verify repair
7 Using the DVM and check the brake switch 1 power
supply circuit.
1. Ignition “Off”, engine “Off”.
2. Remove the brake switch connector from the
brake switch.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
10-14.5V Go to Step 9Go to Step 8 Step Action Value(s) Yes No
301
2 C-56 C-44




Brake Switch
V
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6E–278 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0703 (Symptom Code B) (Flash Code 25)
Brake Switch Circuit Malfunction
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 P0703 (Symptom Code B) 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 P0703 (Symptom Code B) stored in this
ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 Check for poor/faulty connection at the brake switch
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 brake switch 2.
1. Ignition “Off”, engine “Off”.
2. Remove the brake switch connector at the brake
pedal.
3. Check the brake switch 2.
Was the DVM indicated specified value?
Pedal is not
stepped on:
No continuity
Pedal stepped
on: Continuity Go to Step 6Replace pedal
switch and
verify repair
653
4 C-56 C-44




Brake Switch

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–279
6 Using the DVM and check the brake switch 2 power
supply circuit.
1. Ignition “On”, engine “Off”.
2. Remove the brake switch connector from the
brake switch.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
10-14.5V Go to Step 8Go to Step 7
7 Repair the open circuit between the “ECM fuse (10A)”
and brake switch 2.
Is the action complete?—Verify repair—
8 Using the DVM and check the brake switch 2 circuit.
Breaker box is available:
1. Ignition “Off”, engine “Off”.
2. Install the breaker box as type B. (ECM
connected)
3. Ignition “On”, engine “Off”.
4. Check the circuit for open or short to voltage
circuit.
Was the DVM indicated specified value?
Breaker box is not available:
1. Ignition “On”, engine “Off”.
2. Back probe the DVM to the brake switch 2 and
check the circuit for open or short to voltage
circuit.
Was the problem found?
Pedal is not
stepped on:
10-14.5V
Pedal stepped
on: Less than
1V Go to Step 11Fix ed at 10-
14.5V: Go to
Step 9
Fix ed at less
than 1V: Go to
Step 10 Step Action Value(s) Yes No
V
3C-44
65Breaker Box
V
V
4 C-44

6E–282 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0704 (Symptom Code 6) (Flash Code 57)
Clutch Switch Input Circuit Malfunction
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 P0704 (Symptom Code 6) 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 P0704 (Symptom Code 6) stored in this
ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 Check for poor/faulty connection at the clutch switch
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 clutch switch.
1. Ignition “Off”, engine “Off”.
2. Remove the clutch switch connector at the clutch
pedal.
3. Check the clutch switch.
Was the DVM indicated specified value?
Pedal is not
stepped on:
Continuity
Pedal stepped
on: No
continuity Go to Step 6Replace pedal
switch and
verify repair
311
2
C-56 C-77
Clutch Sw itch