P0122

Diagnostic Chart:

CIRCUIT DESCRIPTION

The Throttle Position sensor is potentiometer. A 5 volt reference is provided on CKT 1688 and ground is provided on CKT 808. The TP sensor signal CKT 417 varies between ground and 5 volts based on the position of the throttle plates. At low throttle angle, the TP sensor signal voltage is low. The PCM uses TP sensor information to determine idle, Wide Open Throttle (WOT), deceleration enleanment and acceleration enrichment. DTC P0122 sets when the PCM detects a TP sensor signal that is too low. The PCM tests the TP sensor feedback every 100 ms. If the TP sensor reading is 0.1 volts or less, such as when the signal is open or shorted to ground, the PCM sets DTC P0122.

CONDITIONS FOR RUNNING THE DTC

Engine speed 600 RPM or greater.

CONDITIONS FOR SETTING THE DTC

The TP sensor reading is 0.1 volts or less.

ACTION TAKEN WHEN THE DTC SETS

^ PCM disables the torque converter clutch.

^ PCM calculates a TP sensor value based on MAP and engine speed inputs.

^ PCM disables fourth gear.

^ The PCM will illuminate the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.

^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC

^ The PCM will turn the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.

^ A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.

^ A History DTC will clear after forty consecutive warm-up cycles with no failures of any emission related diagnostic test.

^ PCM battery voltage is interrupted.

^ Using a Scan tool.

DIAGNOSTIC AIDS

If fault is not present perform Powertrain Ground Check and also review Failure Rec. to determine conditions under which and how long ago the DTC set. PCM Power & Ground Check

TEST DESCRIPTION

Number(s) below refer to the step number(s) on the Diagnostic Table.

2. If the TP sensor or circuitry are open, the TP sensor parameter will read 0.1 volts or less.

If fault is not present monitor the scan tool display for this sensor while manipulating the vehicle's electrical harness. A change in sensor output while manipulating the harness may indicate a circuit fault.

3. Checking if circuitry from sensor to PCM is able to respond to a 5 volt signal on the TP input. A reading of 4.5 volts or more means the wiring and the PCM are OK.

17. Disconnect the suspect sensor and re-measure the resistance between the 5 volt reference and sensor ground circuits. If infinite resistance is measured the sensor is shorted.