DTC P0123 Throttle Position (TP)Sensor Circuit High Voltage. Oldsmobile Intrigue 1999

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 Engine 🢒 Engine Controls - 3.5L 🢒 DTC P0123 Throttle Position (TP)Sensor Circuit High Voltage

A/C Refrigerant Pressure Sensor, TP Sensor, Map Sensor, ECT Sensor, IAT sensor
Engine Controls Components
OBD II Symbol Description Notice
ESD Notice

Circuit Description

The throttle position (TP) sensor is a potentiometer. The TP sensor is mounted on the side of the throttle body. The TP sensor provides a voltage signal that changes relative to throttle blade angle. This signal voltage is one of the most important inputs used by the powertrain control module (PCM). The TP sensor has a 5.0 volt reference, a ground, and a signal circuit. The signal voltage varies from below 1 volt at closed throttle to about 4 volts at wide open throttle (WOT).

Conditions for Running the DTC

Engine running.

Conditions for Setting the DTC

•	TP sensor signal voltage is greater than 4.9 volts.

•	Above conditions are present for longer than 1 second

Action Taken When the DTC Sets

•	The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

•

The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

•	The PCM turns the MIL Off after three consecutive drive trips that the diagnostic runs and does not fail.

•	A last test failed (current DTC) clears when the diagnostic runs and does not fail.

•	A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.

•	Use a scan tool in order to clear the MIL/DTC.

•	Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module (PCM) Description , Clearing Diagnostic Trouble Codes.

Diagnostic Aids

Notice: Use the connector test adapter kit J 35616-A for any test that requires probing the following items:

•	The PCM harness connectors

•	The electrical center fuse/relay cavities

•	The component terminals

•	The component harness connector

Using this kit will prevent damage caused by the improper probing of connector terminals.

Check for a malfunctioning TP sensor: With the key ON, engine not running, observe the TP sensor display on the scan tool while slowly depressing the accelerator to wide open throttle. If a voltage over 4.71 volts is seen at any point in normal accelerator travel, replace the TP sensor.

If DTC P0123 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 the problem is intermittent, refer to Intermittent Conditions .

Test Description

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

Components that share the TP sensor 5 volt reference A circuit include the following devices:

•	The EGR valve.

•	The MAP sensor.

•	Disconnect these components one at a time while observing the TP sensor display on the scan tool. If the reading changes drastically when one of these components is disconnected, replace the component that affected the reading.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

Step	Action	Value(s)	Yes	No
1	Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?	--	Go to Step 2	Go to the Powertrain On Board Diagnostic (OBD) System Check
2	With the throttle closed, observe the TP Sensor display on the scan tool. Is TP Sensor greater than the specified value?	4.7 V	Go to Step 4	Go to Step 3
3	Turn the key to Off, wait 15 seconds, then turn the key to On. Review and record scan tool Failure Records data. Operate the vehicle within Failure Records conditions as noted. Using a scan tool, monitor Specific DTC info for DTC P0123. Does scan tool indicate DTC P0123 failed this ign?	--	Go to Step 4	Refer to Diagnostic Aids.
4	Disconnect the TP sensor electrical connector. Observe the TP Sensor display on the scan tool. Is TP Sensor near the specified value?	0 V	Go to Step 5	Go to Step 6
5	Probe the sensor ground circuit at the TP sensor harness connector with test light J 35616-200 connected to B+. Is the test light ON?	--	Go to Step 7	Go to Step 8
6	Turn the key to Off. Disconnect the PCM. Turn the key to On. Check for a short to voltage on the TP sensor signal circuit. If the TP sensor signal circuit is shorted, repair it as necessary. Was a problem found and corrected?	--	Go to Step 13	Go to Step 12
7	Reconnect the TP sensor. Turn the key to On. Monitor the TP Sensor scan tool display while disconnecting each of the components that share the 5 volt reference A circuit (one at a time). Refer to Test Description . If the TP Sensor scan tool display changes, replace the component that caused the display to change when disconnected. Was a problem found and corrected?	--	Go to Step 13	Go to Step 8
8	Turn the key to Off. Disconnect the PCM. Turn the key to On. Check for a short to voltage on the 5 volt reference A circuit. If the 5 volt reference A circuit is shorted, repair it as necessary. Was a problem found and corrected?	--	Go to Step 13	Go to Step 9
9	Check for poor electrical connections at the TP sensor and replace terminals if necessary. Refer to Intermittents and Poor Connections Diagnosis . Was a problem found and corrected?	--	Go to Step 13	Go to Step 11
10	Turn the key to Off. Disconnect the PCM, and check the sensor ground circuit for a poor connection at the PCM or for an open sensor ground circuit to the TP sensor. If a problem is found, repair it as necessary. Refer to Intermittents and Poor Connections Diagnosis . Was a problem found and corrected?	--	Go to Step 13	Go to Step 12
11	Replace the TP sensor. Refer to Throttle Position Sensor Replacement . Is the action complete?	--	Go to Step 13	--
12	Replace the PCM. Important: Replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Is the action complete?	--	Go to Step 13	--
13	Clear DTCs with the scan tool. Turn the key to Off and wait 15 seconds Operate vehicle within the conditions that are required for this diagnostic to run. Refer to Conditions for Running the DTC. Does the scan tool indicate that this test ran and passed?	--	Go to Step 14	Go to Step 2
14	Review Captured Info using the scan tool. Are there any DTCs that have not been diagnosed?	--	Go to the applicable DTC table	System OK