Isuzu 1999 RODEO Workshop Manual page 681

6E1–54
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
7. A Tech 2 parameter which is not within the typical
range may help to isolate the area which is causing
the problem.
On–Board Diagnostic (OBD II) System Check
Step
1 1. Ignition ON, engine OFF.
2. Observe the malfunction indicator lamp (MIL or
"Check Engine lamp").
Is the MIL ("Check Engine lamp") ON?
2 1. Ignition OFF.
2. Install a Tech 2.
3. Ignition ON.
4. Attempt to display PCM engine data with the Tech 2.
Does the Tech 2 display PCM data?
3 1. Using the Tech 2 output tests function, select MIL
dash lamp control and command the MIL OFF.
2. Observe the MIL.
Did the MIL turn OFF?
4 Attempt to start the engine.
Did the engine start and continue to run?
5 Select "Display DTCs" with the Tech 2.
Are any DTCs stored?
6 Are two or more of the following DTCs stored? P0107,
P0113, P0118, P0122, P0123.
7 Compare PCM data values displayed on the Tech 2 to
the typical engine scan data values.
Are the displayed values normal or close to the typical
values?
8 1. Ignition OFF, disconnect the PCM.
2. Ignition ON, engine OFF.
3. Check the Class 2 data circuit for an open, short to
ground, or short to voltage. Also, check the DLC
ignition feed circuit for an open or short to ground
and the DLC ground circuits for an open.
4. If a problem found, repair as necessary.
Was a problem found?
Action
10. This vehicle is equipped with a PCM which utilizes
an electrically erasable programmable read only
memory (EEPROM). When the PCM is replaced,
the new PCM must be programmed. Refer to PCM
Replacement and Programming Procedures in
Powertrain Control Module (PCM) and Sensors.
Value(s)
— Go to Step 2
— Go to Step 3
— Go to Step 4
— Go to Step 5
— Go to Step 6
Information
Sensor DTCs
—
Go to "Typial
Scan" Data
—
— Go to Step 2
Yes No
Go to No MIL
Go to Step 8
Go to MIL
("Check
Engine
Lamp") On
Steady
Go to Cranks
But Will Not
Run
Go to Step 7
Go to
"Multiple
PCM
Go to
applicable
DTC table
Set"
Go to
indicated
Component
System
Value Checks
Go to Step 9