Dtc P0122 -Tp Sensor Circuit Low Voltage - Isuzu Trooper 1999 Workshop Manual

6E–154
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0122 –TP Sensor Circuit Low Voltage
Step
1 Was the "On-Board Diagnostic (OBD) System Check"
performed?
2 1. Ignition "ON," engine "OFF."
2. With the throttle closed, observe the "TP Sensor"
display on the Tech 2.
Is the "TP Sensor" below the specified value?
3 1. Ignition "ON," engine "OFF."
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor the "DTC" info for DTC
P0122.
Does the Tech 2 indicate DTC P0122 failed?
4 1. Ignition "OFF."
2. Disconnect the TP sensor electrical connector.
3. Jumper the 5 volt reference "A" circuit and the TP
signal together at the TP sensor harness connector.
4. Ignition "ON."
Observe the "TP Sensor" display on the Tech 2.(If no,
start with diagnosis chart for other sensors in the circuit
and see if 5V returns.)
Is the "TP Sensor" at the specified value?
5 1. Disconnect jumper.
2. Connect a test light between B+ and the TP sensor
signal circuit at the TP sensor harness connector.
Observe the "TP Sensor" display on the Tech 2.
Is the "TP Sensor" at the specified value? (If no, start
with diagnosis chart for other sensors in the circuit and
see if 5V returns.)
6 1. Ignition "OFF."
2. Disconnect the PCM and check the 5 volt reference
"A" circuit for an open or short to ground.
3. If the 5 volt reference "A" circuit is open or shorted to
ground, repair it as necessary.
Was the 5 volt reference "A" circuit open or shorted to
ground?
7 Check the 5 volt reference "A" circuit for a poor
connection at the PCM and replace the terminal if
necessary.
Did the terminal require replacement?
8 1. Ignition "OFF."
2. Disconnect the PCM, and check the TP signal
circuit for an open, short to ground, or short to the
sensor ground circuit.
3. If the TP sensor signal circuit is open or shorted to
ground, repair it as necessary.
Was the TP signal circuit open or shorted to ground?
Action Value(s) Yes
— Go to Step 2
0.22 V Go to Step 4
— Go to Step 4
5 V Go to Step 10
5 V Go to Step 6
— Verify repair
— Verify repair
— Verify repair
No
Go to OBD
System
Check
Go to Step 3
Refer to
Diagnostic
Aids
Go to Step 5
Go to Step 8
Go to Step 7
Go to Step 12
Go to Step 9