Isuzu 1999 RODEO Workshop Manual page 944

If Diagnostic Trouble Code P1121 cannot be duplicated,
reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help to determine how often
DTC P1121 – TP Sensor Circuit Intermittent High Voltage
Step
1 Was the "On–Board Diagnostic (OBD) System Check"
performed?
2 Is Diagnostic Trouble Code P0123 also set?
3 Is Diagnostic Trouble Code P0463 and/or P1106 also
set?
4 Check for a poor sensor ground circuit terminal
connection at the TP sensor.
Was a problem found?
5 Check the TP signal circuit between the TP sensor
connector and the PCM for an intermittent short to
voltage.
Was a problem found?
6 Check for an intermittent short to voltage on the 5 volt
reference circuit between the PCM and the following
components:
f
MAP Sensor
f
Fuel Tank Vapor Pressure Sensor
Was a problem found?
7 Check for a poor sensor ground terminal connection at
the PCM.
Was a problem found?
8 Check for an intermittent open or a faulty splice in the
sensor ground circuit.
Was a problem found? (if no, start with the diagnosis
chart for other sensors in the circuit and see if 5V
returns.)
9 Replace the faulty harness connector terminal for the
sensor ground circuit.
Is the action complete?
10 Repair intermittent open/short circuit in wiring harness
as necessary.
Is the action complete?
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
Action
the condition that caused the Diagnostic Trouble Code to
be set occurs. This may assist in diagnosing the
condition.
Value(s)
— Go to Step 2
Go to DTC
—
P0123 first
— Go to Step 6
— Go to Step 9
Go to Step
—
Go to Step
—
— Go to Step 9
Go to Step
—
— Verify repair
— Verify repair
6E1–317
Yes No
Go to OBD
System
Check
Go to Step 3
Go to Step 4
Go to Step 5
Go to Step 8
10
Go to Step 7
10
Go to Step 8
Refer to
Diagnostic
Aids
10
—
—