P0122

P0122-THROTTLE POSITION SENSOR 1 CIRCUIT LOW





For a complete wiring diagram refer to Diagrams/Electrical.

- When Monitored:

With the ignition on and battery voltage greater than 10.4 volts.

- Set Condition:

The PCM detects that the Throttle Position Sensor 1 input voltage is below the minimum acceptable value.






Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. DTC IS ACTIVE

Start the engine and allow it to reach normal operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking for an Intermittent DTC

2. (F855) 5 VOLT SUPPLY CIRCUIT VOLTAGE





Turn the ignition off.

Disconnect the Throttle Body connector.

Turn the ignition on.

Measure the voltage of the (F855) 5 Volt Supply circuit in the Throttle Body harness connector.

Is the voltage above 4.5 volts?

Yes

- Go to 6

No

- Go to 3

3. (F855) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND





Turn the ignition on.

Disconnect the Powertrain Control Module (PCM) connector.

Measure the resistance between ground and the (F855) 5 Volt Supply circuit in the Throttle Body harness connector.

Is the resistance above 1000 ohms?

Yes

- Go to 4

No

- Repair the (F855) 5 Volt Supply circuit for a short to ground.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

4. (F855) 5 VOLT SUPPLY CIRCUIT SHORTED TO (K922) TP SENSOR GROUND CIRCUIT





Measure the resistance between the (F855) 5 Volt Supply circuit and the (K922) TP Sensor Ground circuit in the Throttle Body harness connector.

Is the resistance above 100 ohms?

Yes

- Go to 5

No

- Repair the (F855) 5 Volt Supply circuit for a short to the (K922) TP Sensor Ground circuit.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

5. (F855) 5 VOLT SUPPLY CIRCUIT OPEN OR HIGH RESISTANCE





Measure the resistance of the (F855) 5 Volt Supply circuit between the Throttle Body harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go to 12

No

- Repair the (F855) 5 Volt Supply circuit for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

6. (K22) TP SIGNAL 1 CIRCUIT SHORTED TO GROUND





Turn the ignition off.

Disconnect the Powertrain Control Module (PCM) connector.

Measure the resistance between ground and the (K22) TP Signal 1 circuit in the Throttle Body harness connector.

Is the resistance above 100 ohms?

Yes

- Go to 7

No

- Repair the (K22) TP Signal 1 circuit for a short to ground.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

7. (K22) TP SIGNAL 1 CIRCUIT SHORTED TO (K922) TP SENSOR GROUND CIRCUIT





Measure the resistance between the (K22) TP Signal 1 circuit and the (K922) TP Sensor Ground circuit in the Throttle Body harness connector.

Is the resistance above 100 ohms?

Yes

- Go to 8

No

- Repair the (K22) TP Signal 1 circuit for a short to the (K922) TP Sensor Ground circuit.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

8. (K22) TP SIGNAL 1 CIRCUIT SHORTED TO THE (K124) ETC MOTOR (+) CIRCUIT





Measure the resistance between the (K22) TP Signal 1 circuit and the (K124) ETC Motor (+) in the Throttle Body harness connector.

Is the resistance below 100 ohms?

Yes

- Repair the (K124) ETC Motor (+) circuit for a short to the (K22) TP Signal 1 circuit.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to 9

9. (K22) TP SIGNAL 1 CIRCUIT SHORTED TO THE (K126) ETC MOTOR (-) CIRCUIT





Measure the resistance between the (K22) TP Signal 1 circuit and the (K126) ETC Motor (-) in the Throttle Body harness connector.

Is the resistance below 100 ohms?

Yes

- Repair the (K22) TP Signal 1 circuit for a short to the (K126) ETC Motor (-) circuit.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to 10

10. (K22) TP SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE





Measure the resistance of the (K22) TP Signal 1 circuit between the Throttle Body harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go to 11

No

- Repair the (K22) TP Signal 1 circuit for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

11. THROTTLE BODY





Turn the ignition off.

Connect the Powertrain Control Module (PCM) connector.

Connect a jumper wire between the (F855) 5 Volt Supply circuit and the (K22) TP Signal 1 circuit in the Throttle Body harness connector.

Turn the ignition on.

With the scan tool, read the TP Signal 1 circuit voltage.

Is the voltage above 4.5 volts with the jumper wire in place?

Yes

- Replace the Throttle Body.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to 12

12. POWERTRAIN CONTROL MODULE (PCM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals.

Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.

Look for the data to change or for the DTC to reset during the wiggle test.

Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test Ver. 1. PCM Verification Test