DTC P0122 Throttle Position (TP) Sensor Circuit Low Voltage. Oldsmobile Intrigue 1999

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 DTC P0122 Throttle Position (TP) Sensor Circuit Low Voltage

Engine Controls Components
Engine Data Sensors
OBD II Symbol Description Notice

Circuit Description

The Throttle Position (TP) sensor circuit provides a voltage signal that changes relative to throttle blade angle. The signal voltage will vary from less than 1 volt at closed throttle to about 4 volts at Wide Open Throttle (WOT). The TP signal is one of the most important inputs used by the PCM for fuel control and most of the PCM-controlled outputs. The PCM monitors throttle position and compares actual throttle position from the TP sensor to a predicted TP value calculated from engine speed. If the PCM detects an excessively low TP sensor signal voltage, DTC P0122 will be set.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

•	TP sensor signal voltage is less than 0.1 volt.

•	Above conditions are present for longer than 1 second.

Action Taken When the DTC Sets

•	The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.

•	The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.

Conditions for Clearing the MIL/DTC

•	The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.

•	The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

•	The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

Diagnostic Aids

Check for the following conditions:

•	Poor connection at PCM. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection

•	Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the throttle position display on the scan tool while moving connectors and wiring harnesses related to the TP sensor. A change in the display will indicate the location of the malfunction.

If DTC P0122 cannot be duplicated, the information included in the Fail Records data can be useful in determining vehicle mileage since the DTC was last set. If it is determined that the DTC occurs intermittently, performing the DTC P1122 Diagnostic Chart may isolate the cause of the malfunction.

Test Description

The number(s) below refer to the step number(s) on the Diagnostic Table:

This vehicle is equipped with a powertrain control module (PCM) which utilizes an electrically erasable programmable read-only memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.

DTC P0122 - TP Sensor Circuit Low Voltage

Step	Action	Value(s)	Yes	No
1	Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?	--	Go to Step 2	Go to Powertrain On Board Diagnostic (OBD) System Check
2	Turn on the ignition switch with the engine not running. With the throttle closed, observe the throttle position (TP) sensor display on the scan tool. Is the voltage less than the specified value?	0.16 V	Go to Step 4	Go to Step 3
3	Turn on the ignition switch. Review and record the scan tool Fail Records data. Operate the vehicle within the Fail Records conditions as noted. Use the scan tool in order to monitor the Specific DTC info for DTC P0122. Does the scan tool indicate DTC P0122 failed?	--	Go to Step 4	Go to Diagnostic Aids
4	Disconnect the TP sensor electrical connector. Jumper the 5 volt reference A circuit and the TP signal together at the TP sensor harness connector. Observe the TP Sensor display on the scan tool. Does the voltage equal the specified value?	5 V	Go to Step 11	Go to Step 5
5	Connect a test lamp between B+ and the TP sensor signal circuit at the TP sensor harness connector Observe the TP Sensor display on the scan tool. Does the voltage equal the specified value?	5 V	Go to Step 6	Go to Step 8
6	Turn off the ignition switch. Disconnect the PCM. Test the 5 volt reference A circuit for an open or short to ground. If the 5 volt reference A circuit is open or shorted to ground, repair as necessary. Refer to Wiring Repairs in Wiring Systems. Was a problem found?	--	Go to Step 14	Go to Step 7
7	Test the 5 volt reference A circuit for a faulty connection at the PCM. If a problem is found repair as necessary. Refer to Wiring Repairs in Wiring Systems. Was a problem found?	--	Go to Step 14	Go to Step 13
8	Turn off the ignition switch. Disconnect the PCM. Test the 5 volt reference A circuit for a short to ground or for a short to the sensor ground circuit. If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems. Was a problem found?	--	Go to Step 14	Go to Step 9
9	Turn off the ignition switch. Disconnect the PCM. Test the TP signal circuit for an open, a short to ground, or a short to the sensor ground circuit. If the TP sensor signal circuit is open or shorted to ground, repair as necessary. Refer to Wiring Repairs in Wiring Systems. Was a problem found?	--	Go to Step 14	Go to Step 10
10	Check the TP sensor signal circuit for a poor connection at the PCM If a problem is found, repair as necessary. Refer to Wiring Repairs . Was a problem found?	--	Go to Step 14	Go to Step 13
11	Test the TP sensor signal circuit for a faulty connection at the TP sensor. If a problem is found, replace the terminal. Refer to Connector Repairs in Wiring Systems. Was a problem found?	--	Go to Step 14	Go to Step 12
12	Replace the TP sensor. Refer to Throttle Position Sensor Replacement Did you complete the repair?	--	Go to Step 14	--
13	Important: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming Replace the PCM. Did you complete the repair?	--	Go to Step 14	--
14	Review and record the scan tool Fail Records data. Clear any DTCs Operate the vehicle within the Fail Records conditions as noted. Use the scan tool in order to monitor the Specific DTC info for DTC P0122. Does the scan tool indicate DTC P0122 failed?	--	Go to Step 4	System OK