Circuit Description
The Throttle Position (TP) sensor provides a voltage signal that changes relative to the throttle opening. The TP sensor signal voltage varies from about 0.35 volt at idle to about 4.65 volts at Wide Open Throttle (WOT). The TP sensor signal input is used by the ECU for fuel trim and diagnostic functions.
This is a type B DTC.
Conditions for Setting the DTC
| • | The vehicle is in the CNG operation mode. |
| • | The engine is running. |
| • | The TP sensor circuit voltage is less than 0.09 volt. |
Action Taken When the DTC Sets
The ECU sets the DTC 22 after two consecutive driving cycles with the fault active.
Conditions for Clearing the MIL/DTC
The ECU turns the MIL off after three consecutive driving trips without a fault condition present. A DTC will clear if no fault conditions have been detected for 40 warm-up cycles (coolant temperature has risen 72°F (40°C) from the start-up coolant temperature and the engine coolant temperature exceeds 160°F (70°C) during that same ignition cycle) or the code clearing procedure has been used.
Diagnostic Aids
Always diagnose ANY PCM codes that are present before beginning this diagnostic procedure.
A scan tool displays the throttle position in volts. It should display 0.35 volt to 0.90 volt with the throttle closed and the ignition ON or at idle. The voltage should increase at a steady rate as the throttle is moved toward Wide Open Throttle (WOT). Also, the scan tool displays the throttle angle percentage where 0% = closed and 100% = WOT.
Scan the TP sensor signal while depressing the accelerator pedal with the engine stopped and the ignition ON. The display should vary from below 1.25 volts when the throttle is closed to over 4.5 volts when the throttle is held in the Wide Open Throttle (WOT) position.
This DTC will result if the TP signal circuit is shorted to the ground.
If the DTC is intermittent, refer to Intermittent Conditions .
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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If the TP sensor signal measures less than 0.24 volt, the fault exists.
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This test determines if the fault exists in the ECU or the PCM wiring.
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This test simulates DTC 21 (high voltage). If the ECU recognizes the high signal voltage, the wiring and the ECU are OK.
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If the resistance of the LPL is out of range, the ground offset between the PCM and the AF ECU will increase. This will cause the ECU to detect a false low voltage condition.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the AF Powertrain OBD System Check performed? | -- | Go to Step 2 | Go to Alternative Fuels (AF) Powertrain On Board (OBD) System Check |
Does the scan tool display a throttle position signal less than the specified value? | 0.24 V | Go to Step 3 | Go to Step 6 | |
Disconnect ECU connector C001. Does the scan tool display a throttle position signal less than the specified value? | 0.24 V | Go to Step 4 | Go to Step 8 | |
Does the scan tool display a throttle position signal greater than the specified value? | 4.0 V | Go to Step 18 | Go to Step 5 | |
5 | Connect a test lamp between B+ and the TP sensor signal circuit at the TP sensor electrical connector. Does the scan tool display a throttle position signal over the specified value? | 4.0 V | Go to Step 12 | Go to Step 14 |
6 |
Does the DVOM display the TP sensor signal less than the specified value? | 0.24 V | Go to Step 7 | Go to Step 11 |
7 |
Is there continuity? | -- | Go to Step 8 | Go to Step 16 |
8 |
Was a problem found? | -- | Go to Step 16 | Go to Step 9 |
Inspect the resistance of the low pressure lock-off (LPL) coil. Is the resistance within the specified range? | 6.2 ohms - 10 ohms | Go to Step 10 | Go to Step 17 | |
10 | Replace the ECU. Refer to Engine Control Unit Replacement . Is the action complete? | -- | Go to Step 20 | -- |
11 | The DTC is intermittent. If no additional DTCs are stored, refer to the Diagnostic Aids. If additional DTCs are stored, refer to those tables. Are any additional DTCs set? | -- | Go to the applicable DTC table | Go to Diagnostic Aids |
12 | Inspect for an open or short to ground in the 5 volt reference circuit. Was a problem found? | -- | Go to Step 16 | Go to Step 13 |
13 | Inspect the 5 volt reference circuit for a poor electrical connection at the PCM. Was a problem found? | -- | Go to Step 16 | Go to Step 19 |
14 | Inspect the TP sensor signal for an open or a short to ground. Was a problem found? | -- | Go to Step 16 | Go to Step 15 |
15 | Inspect the TP sensor signal circuit for a poor connection at the PCM. Was a problem found? | -- | Go to Step 16 | Go to Step 19 |
16 | Repair the circuit as needed. Refer to Wiring Repairs in Engine Electrical in the J Platform Service Manual. Is the repair complete? | -- | Go to Step 20 | -- |
17 | Replace the LPL. Refer to Low Pressure Lock-Off Solenoid Replacement . Is the action complete? | -- | Go to Step 20 | -- |
18 | Replace the faulty TP Sensor. Refer to TP Sensor Replacement in Engine Controls - 2.2L in the J Platform Service Manual. Is the action complete? | -- | Go to Step 20 | -- |
19 |
Is the action complete? | -- | Go to Step 20 | -- |
20 |
Did the diagnostic run and pass? | -- | Go to Step 21 | Go to Step 3 |
21 | Using the scan tool, select Capture Information and review. Are any DTCs displayed that have not been diagnosed? | -- | Go to the applicable DTC table | System OK |
