Isuzu KB P190. Manual — part 299

6E-162 Engine Control System (4JH1)

Step Action

Value(s)

Yes

No

11

Replace the IPC (meter assembly). Refer to Meter
Replacement in electrical section.
Did you complete the replacement?



Go to Step 14



12

Important: Replacement TCM must be
programmed.
Replace the TCM. Refer to Transmission Control
Module (TCM) Replacement in the transmission
section.
Did you complete the replacement?



Go to Step 14



13

Important: Replacement ECM must be
programmed.
Replace the ECM. Refer to Engine Control Module
(ECM) Replacement in this section.
Did you complete the replacement?



Go to Step 14



14

1. Reconnect all previously disconnected harness

connector(s).

2. Clear the DTCs with the scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Drive the vehicle.
5. Observe the Vehicle Speed parameter with the

scan tool.

Does the Vehicle Speed parameter indicate correct
vehicle speed?



Go to Step 15

Go to Step 2

15

Observe the DTC Information with the scan tool.
Are there any DTCs that you have not diagnosed?



Go to Diagnostic

Trouble Code (DTC)

List System

OK

Chart for except 2WD with A/T

Step Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check-
Engine Controls?



Go to Step 2

Go to Diagnostic

System Check-

Engine Controls

2

1. Install the scan tool.
2. Drive the vehicle.
3. Observe the Vehicle Speed parameter with the

scan tool.

Does the Vehicle Speed parameter indicate correct
vehicle speed?



Go to Diagnostic

Aids

Go to Step 3

3

1. Turn OFF the ignition.
2. Inspect the Meter (15A) fuse (C-14) in the cabin

fuse block.

Is the Meter (15A) fuse (C-14) open?



Go to Step 4

Go to Step 5

4

Replace the Meter (15A) fuse (C-14). If the fuse
continues to open, repair the short to ground on one
of the circuits that fed by the Meter (15A) fuse (C-14)
or replace the shorted attached component fed by
the Meter (15A) fuse (C-14).
Did you complete the repair?



Go to Step 20



Engine Control System (4JH1) 6E-163

Step Action

Value(s)

Yes

No

5

1. Remove the vehicle speed sensor (VSS). Refer

to Vehicle Speed Sensor (VSS) Replacement in
this section.

2. Visually inspect the VSS for the following

conditions:

• Physical

damage

• Being

loose

• Improper

installation

• For transmission output shaft teeth damage

3. Repair or replace as necessary.
Did you find and correct the condition?



Go to Step 20

Go to Step 6

6

1. Turn OFF the ignition.
2. Disconnect the VSS harness connector.
3. Connect a test lamp between the ignition voltage

feed circuit of the VSS harness (pin 1 of E-44
connector) and a known good ground.

4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?



Go to Step 7

Go to Step 9

7

1. Turn ON the ignition, with the engine OFF.
2. Connect a test lamp between the ignition voltage

feed circuit and low reference circuit of the VSS
harness (pins 1 and 2 of E-44 connector).

Does the test lamp illuminate?



Go to Step 8

Go to Step 10

8

1. Turn ON the ignition, with the engine OFF.
2. Intermittently jump the signal circuit of the VSS

(pin 3 of E-44 connector) with a test lamp that is
connected to a known good ground while
monitoring the Vehicle Speed parameter with the
scan tool.

Does the scan tool indicate any vehicle speed when
the circuit is intermittently pulled to ground?



Go to Step 14

Go to Step 11

9

Repair the open or high resistance in the VSS
ignition voltage feed circuit between the Meter (15A)
fuse (C-14) and the VSS (pin 1 of E-44 connector).
Did you complete the repair?



Go to Step 20



10

Repair the open or high resistance in the VSS low
reference circuit between the VSS (pin 2 of E-44
connector) and the chassis ground.
Did you complete the repair?



Go to Step 20



11

1. Turn OFF the ignition.
2. Remove the instrument panel cluster (IPC) in

order to disconnect the B-24 harness connector.

3. Disconnect the IPC B-24 harness connector.
4. Turn ON the ignition, with the engine OFF.
5. Intermittently jump the signal output circuit of the

VSS signal (pin 10 of B-24 connector) with a test
lamp that is connected to a known good ground
while monitoring the Vehicle Speed parameter
with the scan tool.

Does the scan tool indicate any vehicle speed when
the circuit is intermittently pulled to ground?



Go to Step 12

Go to Step 13

6E-164 Engine Control System (4JH1)

Step Action

Value(s)

Yes

No

12

1. Test the VSS signal circuit between the VSS (pin

3 of E-44 connector) and the IPC (pin 9 of B-23
connector) for the following conditions:

• An open circuit
• A short to ground
• A short to battery or ignition voltage
• High

resistance

2. Repair the circuit(s) as necessary.
Did you find and correct the condition?



Go to Step 20

Go to Step 15

13

1. Test the VSS signal circuit between the engine

control module (ECM) (pin 68 of C-56 connector)
and the IPC (pin 10 of B-23 connector) for the
following conditions:

• An open circuit
• A short to ground
• A short to battery or ignition voltage
• High

resistance

2. Repair the circuit(s) as necessary.
Did you find and correct the condition?



Go to Step 20

Go to Step 16

14

1. Turn OFF the ignition.
2. Disconnect the VSS harness connector.
3. Inspect for an intermittent and for poor

connections at the harness connector of the VSS
(pin 1, 2 and 3 of E-44 connector).

4. Repair the connection(s) as necessary.
Did you find and correct the condition?



Go to Step 20

Go to Step 17

15

1. Turn OFF the ignition.
2. Disconnect the IPC B-23 harness connector.
3. Inspect for an intermittent and for poor

connections at the harness connector of the IPC
(pins 9 and 10 of B-23 connector).

4. Repair the connection(s) as necessary.
Did you find and correct the condition?



Go to Step 20

Go to Step 18

16

1. Turn OFF the ignition.
2. Disconnect the ECM harness connector.
3. Inspect for an intermittent and for a poor

connection on the VSS signal circuit at the
harness connector of the ECM (pin 68 of C-56
connector).

4. Repair the connection(s) as necessary.
Did you find and correct the condition?



Go to Step 20

Go to Step 19

17

Replace the VSS. Refer to Vehicle Speed Sensor
(VSS) Replacement in this section.
Did you complete the replacement?



Go to Step 20



18

Replace the IPC (meter assembly). Refer to Meter
Replacement in electrical section.
Did you complete the replacement?



Go to Step 20



19

Important: Replacement ECM must be
programmed.
Replace the ECM. Refer to Engine Control Module
(ECM) Replacement in this section.
Did you complete the replacement?



Go to Step 20



Engine Control System (4JH1) 6E-165

Step Action

Value(s)

Yes

No

20

1. Reconnect all previously disconnected fuse or

harness connector(s).

2. Clear the DTCs with the scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Drive the vehicle.
5. Observe the Vehicle Speed parameter with the

scan tool.

Does the Vehicle Speed parameter indicate correct
vehicle speed?



Go to Step 21

Go to Step 3

21

Observe the DTC Information with the scan tool.
Are there any DTCs that you have not diagnosed?



Go to Diagnostic

Trouble Code (DTC)

List System

OK