DTC 22

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

TPS Sensor, ECT Sensor, IAT Sensor Wiring Circuit:

Circuit Description:

The Throttle Position (TP) sensor provides a voltage signal that changes relative to throttle blade angle. Signal voltage will vary from about .4 at idle to above 4 volts at Wide Open Throttle (WOT).

The TP sensor signal is one of the most important inputs used by the PCM for fuel control and for most of the PCM control outputs. DTC 22 will set if:
^ The ignition key is "ON."
^ TP sensor signal voltage is less than .2 volt for 4 seconds.

Test Description: Number(s) below refer to circled number(s) on the diagnostic chart.
1. Determines if conditions necessary to set DTC 22 exist.
2. Simulates DTC 21: (high voltage) If PCM recognizes the high signal voltage and sets DTC 21, the PCM and wiring are OK.
3. With closed throttle, ignition "ON" or at idle, voltage at "BB10" should be .20-.74 volt. If not, replace TP sensor.
4. Simulates a high signal voltage. Checks CKT 417 for an open.

NOTICE: If DTC 22 is set, the PCM will not allow 4th gear, cruise control, or TCC operation.

Diagnostic Aids:

The Tech 1 displays throttle position in volts. 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.

If CKT 417 is open or grounded when the vehicle engine is started, a high idle may result. The Tech 1 may read the following with CKT 417 open or grounded:

TP sensor = .04 volt or less
RPM > 1000 in park
Desired idle = 725
IAC counts> 40
MIL (Service Engine Soon) "ON" DTC 22 set

If the intermittent is repaired without cycling the key "OFF," the Tech 1 may read the following:
TP sensor = .42 volt
RPM > 1500 in park
Desired idle = 725
IAC counts > 55
MIL "OFF"

Check for:
^ Poor Connection or Damaged Harness - Inspect PCM harness connectors for backed out terminal "BB1O" and/or "BB3", improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness.
^ Intermittent Test - Monitor TP sensor voltage display while moving related connectors and wiring harness. If the failure is induced, the display will change. This may help to isolate the location of the malfunction.
^ TP Sensor Scaling - Observe TP sensor voltage display while depressing accelerator pedal with engine stopped and ignition "ON." Display should vary from closed throttle TP sensor voltage .20-.74 to over 4.0 volts when throttle is held at Wide Open Throttle (WOT) position.