2012 Jeep Wrangler JK Factory Service Manual 28 - DTC-Based Diagnostics

P0222-THROTTLE POSITION SENSOR 2 CIRCUIT LOW

P0222-THROTTLE POSITION SENSOR 2 CIRCUIT LOW

For a complete wiring diagram, refer to the Wiring Information.


Theory of operation

The Electronic Throttle Control (ETC) system uses two Throttle Position Sensors (TPS) to monitor the throttle blade position. The Throttle Position Sensors 1 and 2 are located within the Throttle Body assembly. Each sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. Processors are also used to monitor the ETC system data. The processors are located within the Powertrain Control Module (PCM). Each signal circuit provides the processors with a signal voltage proportional to throttle blade movement. The processors share and monitor data to verify that the indicated TPS calculation is correct.


Possible Causes

(F855) 5 VOLT SUPPLY CIRCUIT OPEN
(F855) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND
(K122) TP SENSOR NO.2 SIGNAL CIRCUIT SHORTED TO GROUND
(K122) TP SENSOR NO.2 SIGNAL CIRCUIT SHORTED TO THE (K922) TP SENSOR RETURN CIRCUIT
THROTTLE POSITION SENSOR/THROTTLE BODY
THROTTLE PLATE JAMMED AGAINST THE MAXIMUM STOP
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).


1. ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)



NOTE: When this DTC is Active the engine speed, torque and vehicle speed are limited to a Limp in mode.

NOTE: If a 5 Volt supply DTC has also set, diagnose the 5 volt DTC before continuing.

NOTE: If P2101 is also set, then make sure that the blade moves freely and does not hang up near Wide Open Throttle, by performing the Throttle Follower Test before trying to repair P0222.
1. Ignition on, engine not running.
2. Using the scan tool, read the active DTCs.


Is the DTC Active at this time?

Yes


No


2. P0122 ALSO SET



Was the P0122-TP SENSOR NO.1 VOLTAGE LOW DTC set along with the P0222?

Yes


No


3. (F855) 5-VOLT SUPPLY CIRCUIT
1. Turn the ignition off.
2. Disconnect the Throttle Body harness connector.
3. Ignition on, engine not running.
4. Measure the voltage on the (F855) 5-volt Supply circuit in the Throttle Body harness connector.


Is the voltage between 4.8 to 5.2 volts?

Yes


No


4. THROTTLE POSITION SENSOR

1. Connect a jumper wire between the (F855) 5-volt Supply circuit and the (K122) TP Sensor No.2 Signal circuit in the Throttle Body harness connector.
2. Using the scan tool, monitor the TP Sensor No.2 voltage.


Is the voltage between 4.8 and 5.2 volts with the jumper wire installed?

Yes


No


5. (K122) TP SENSOR NO.2 SIGNAL CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance of the (K122) TP Sensor No.2 Signal circuit from the Throttle Body harness connector to the PCM C2 harness connector.


Is the resistance below 5.0 Ohms?

Yes


No


6. (K122) TP SENSOR NO.2 SIGNAL CIRCUIT SHORTED TO GROUND
1. Measure the resistance between ground and the (K122) TP Sensor No.2 Signal circuit at the Throttle Body harness connector.


Is the resistance below 100 Ohms?

Yes


No


7. (K122) TP SENSOR NO.2 SIGNAL CIRCUIT SHORTED TO THE (K922) TP SENSOR RETURN CIRCUIT
1. Measure the resistance between the (K122) TP Sensor No.2 Signal circuit and the (K922) TP Sensor Return circuit at the Throttle Body harness connector.


Is the resistance below 100 Ohms?

Yes


No


8. (F855) 5-VOLT SUPPLY CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance of the (F855) 5-volt Supply circuit from the Throttle Body harness connector to the PCM C2 harness connector.


Is the resistance below 5.0 Ohms?

Yes


No


9. (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
1. Measure the resistance between ground and the (F855) 5-volt Supply circuit at the Throttle Body harness connector.


Is the resistance below 100 Ohms?

Yes


No


10. POWERTRAIN CONTROL MODULE (PCM)

1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.


Were there any problems found?

Yes


No


11. THROTTLE FOLLOWER TEST

1. Ignition on, engine not running.
2. Using the scan tool, perform the ETC Throttle Follower Test.
3. Monitor the TP Sensor No.2 voltage while slowly pressing the Throttle pedal down.


Is there a smooth voltage change from approximately 4.3 volts and decrease to approximately 0.7 volt?

Yes


No