Page 973 of 5267
10.EXCESSIVE RESISTANCE IN THE (F855) 5-VOLT SUPPLY CIRCUIT
Turn the ignition off.
Disconnect the MAP Sensor harness connector.
Disconnect the PCM harness connectors.
Measure the resistance of the (F855) 5-volt Supply circuit from the MAP
Sensor harness connector to the PCM harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 11
No>>
Repair the excessive resistance in the (F855) 5-volt Supply
circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
11 .MAP (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (F855) 5-volt Supply
circuit at the MAP Sensor harness connector.
Is the resistance above 100k ohms?
Ye s>>
Go To 12
No>>
Repair the short to ground in the (F855) 5-volt Supply cir-
cuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
Page 974 of 5267

12.MAP SENSOR
Connect the PCM harness connectors.
Ignition on, engine not running.
With the scan tool, monitor the MAP Sensor voltage.
Connect a jumper wire between the (K1) MAP Sensor Signal circuit and
the (K900) Sensor ground circuit.
Cycle the ignition switch from off to on.
Did the voltage change from approximately 4.9 volts to below
0.5 of a volt with the jumper wire inst
Ye s>>
Replace the MAP Sensor.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 13
NOTE: Remove the jumper wire before continuing.
13.EXCESSIVE RESISTANCE IN THE (K1) MAP SENSOR SIGNAL CIRCUIT
Turn the ignition off.
Disconnect the PCM harness connectors.
Measure the resistance of the (K1) MAP Sensor Signal circuit from the
MAP Sensor harness connector to the PCM harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 14
No>>
Repair the excessive resistance in the (K1) MAP Sensor
Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
Page 975 of 5267

14.SHORT TO GROUND IN THE (K1) MAP SENSOR SIGNAL CIRCUIT
Measure the resistance between ground and the (K1) MAP Sensor Sig-
nal circuit at the MAP Sensor harness connector.
Istheresistancebelow100ohms?
Ye s>>
Go To 15
No>>
Repair the short to ground in the (K1) MAP Sensor Signal
circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
15.RESISTANCE IN MAP (K900) SENSOR GROUND CIRCUIT
Measure the resistance of the (K900) Sensor ground circuit from the
MAP Sensor harness connector to the PCM harness connector.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 16
No>>
Repair the excessive resistance in the (K900) Sensor
ground circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
16.PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.
If there are no possible causes remaining, view repair.
Repair
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 976 of 5267
P0122-THROTTLE POSITION SENSOR #1 VOLTAGE TOO LOW
For a complete wiring diagramRefer to Section 8W.
Page 977 of 5267

When Monitored:
With the ignition on. Battery voltage greater than 10.4 volts.
Set Condition:
Throttle Position Sensor voltage at the PCM is less than 0.1 of a volt for 1.3seconds.
Possible Causes
(F855) 5-VOLT SUPPLY CIRCUIT OPEN
(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
(K22) TP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO GROUND
(K22) TP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO THE (K900) SENSOR GROUND CIRCUIT
THROTTLE POSITION SENSOR
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.THROTTLE POSITION SENSOR VOLTAGE BELOW 0.098 OF A VOLT
Ignition on, engine not running.
With a scan tool, read the TP Sensor voltage.
Is the voltage below 0.2 of a volt?
Ye s>>
Go To 2
No>>
Go To 9
2.(F855) 5-VOLT SUPPLY CIRCUIT
Turn the ignition off.
Disconnect the TP Sensor harness connector.
Ignition on, engine not running.
Measure the voltage on the (F855) 5-volt Supply circuit in the TP Sen-
sor harness connector.
Is the voltage between 4.5 to 5.2 volts?
Ye s>>
Go To 3
No>>
Go To 6
3.THROTTLE POSITION SENSOR
With the a scan tool, monitor the TP Sensor voltage with the Sensor harness connector disconnected.
Is the voltage above 4.5 volts?
Ye s>>
ReplacetheThrottlePositionSensor.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 4
Page 978 of 5267
4.(K22) TP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the C2 PCM harness connector.
Measure the resistance between ground and the (K22) TP Sensor Sig-
nal circuit in the TP Sensor harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (K22) TP Sensor Signal
circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 5
5.(K22) TP SENSOR NO.1 SIGNAL CIRCUIT SHORTED TO THE (K900) SENSOR GROUND CIRCUIT
Measure the resistance between the (K22) TP Sensor Signal circuit and
the (K900) Sensor ground circuit in the TP Sensor harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short between the (K900) Sensor ground and the
(K22) TP Sensor Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 8
Page 979 of 5267

6.(F855) 5-VOLT SUPPLY CIRCUIT OPEN
Turn the ignition off.
Disconnect the PCM harness connector.
Measure the resistance of the (F855) 5-volt Supply circuit from the TP
Sensor harness connector to the appropriate terminal of the PCM.
Is the resistance below 5.0 ohms?
Ye s>>
Go To 7
No>>
Repair the open in the (F855) 5-volt Supply circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
7.(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
Measure the resistance between ground and the (F855) 5-volt Supply
circuit in the TP Sensor harness connector.
Istheresistancebelow100ohms?
Ye s>>
Repair the short to ground in the (F855) 5-volt Supply cir-
cuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 8
8.PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Replace and program the Powertrain Control Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
Page 980 of 5267
9.THROTTLE POSITION SENSOR SWEEP
With a scan tool, monitor the Throttle Position Sensor voltage.
Slowly open the throttle from the idle position to the wide open throttle position.
Does voltage start at approximately 0.8 of a volt and go above 3.5 volts witha smooth transition?
Ye s>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
ReplacetheThrottlePositionSensor.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)