Powertrain Controls - ECM/PCM

DTC 22 Throttle Position (TP) Sensor Circuit Low (Signal Voltage Low):

Throttle Position (TP) Circuit:

CIRCUIT DESCRIPTION
The Throttle Position (TP) sensor provides a voltage signal that changes relative to the throttle blade. Signal voltage will vary from about 0.5 volt at idle to about 4.0 volts at Wide Open Throttle (WOT).

The TP signal is one of the most important inputs used by the Powertrain Control Module (PCM) for fuel control and for most of the PCM control outputs.

DTC 22 WILL SET WHEN
^ Engine running.
^ TP signal voltage is less than 0.2 volt for 1 second.

ACTION TAKEN (PCM WILL DEFAULT TO)
The Malfunction Indicator Lamp (MIL) will illuminate, transmission Torque Converter Clutch (TCC) will not apply, high transmission line pressure, hard shifts, fixed shift points and no fourth gear in hot mode.

DTC 22 WILL CLEAR WHEN
Conditions for fault are no longer present and Tech 1 "Clear DTCs" function is used or 50 ignition switch keycycles have passed with no further faults or ignition switch is turned "OFF" and fuse #9 fuse is removed for 10 seconds.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This step determines if DTC 22 is the result of a hard failure or an intermittent condition.
2. Simulates DTC 21: (high voltage) If the PCM recognizes the high signal voltage the PCM and wiring are OK.
3. This step determines a poor connection or faulty TP sensor.
4. This simulates a high signal voltage to check for an open in CKT 417.

DIAGNOSTIC AIDS
A Tech 1 scan tool reads throttle position in volts and should read about 0.45 to 0.85 volt with throttle closed and ignition "ON" or at idle. Voltage should increase at a steady rate as throttle is moved toward WOT.

An open or short to ground in CKT 416 or 417 will result in a DTC 22.

Refer to Intermittents. - Intermittent Malfunctions

Scan TP sensor while depressing accelerator pedal with engine stopped and ignition "ON." Display should vary from below 0.85 volt (850 mV) when throttle was closed, to over 4.0 volts (4000 mV) when throttle is held at Wide Open Throttle (WOT) position.