LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volvo >> 1998 >> S90 AW30-40 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Diagnostic Tests >> DTC 411: Throttle Position Sensor Signal
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC 411: Throttle Position Sensor Signal

  1. Check status message on Volvo Scan Tool (998-8686 ). If status message is PERMANENT FAULT, SIGNAL TOO HIGH, go to next step. If status message is PERMANENT FAULT, SIGNAL TOO LOW, go to step 9). If status message is INTERMITTENT FAULT, SIGNAL TOO HIGH, go to step 13). If status message is INTERMITTENT FAULT, SIGNAL TOO LOW, go to step 15).
  2. Turn ignition off. Wait about 2 minutes. If engine cooling fan is running, wait for it to switch off. Disconnect TP sensor. Connect ohmmeter between TP sensor connector terminal No. 1 and ground. If ohmmeter reads about zero ohms, go to next step. If ohmmeter does not read about zero ohms, go to step 4).
  3. Turn ignition off. Disconnect TP sensor. Disconnect ECM. Clean ECM connector of oxidation or other contact resistance. Reconnect ECM. Connect an ohmmeter between TP sensor connector terminal No. 1 and ground. If ohmmeter reads about zero ohms, DTC is caused by poor contact at ECM connector. If ohmmeter does not read about zero ohms, check wiring between TP sensor connector terminal No. 1 and ECM connector terminal A18 for an open circuit.
  4. Turn ignition on. Disconnect TP sensor. Connect voltmeter between TP sensor connector terminal No. 2 and ground. If voltmeter reads about 5 volts, go to next step. If voltmeter does not show about 5 volts, check wiring between TP sensor connector terminal No. 2 and ECM connector terminal A15 for a short circuit to voltage.
  5. Turn ignition on. Disconnect TP sensor. Connect voltmeter between TP sensor connector terminal No. 3 and ground. If voltmeter reads about 6 volts, go to step 7). If voltmeter reads about zero volts, go to next step. If voltmeter reads more than about 6 volts, check wiring between TP sensor connector terminal No. 3 and ECM connector terminal A16 for a short circuit to voltage. If wiring is okay, go to step 8).
  6. Turn ignition off. Disconnect TP sensor. Disconnect ECM connector. Ensure ECM connector terminals are clean and tight. Reconnect ECM. Turn ignition on. Connect voltmeter between TP sensor connector terminal No. 3 and ground. If voltmeter reads about 6 volts, DTC was caused by poor contact at ECM connector. If voltmeter does not read about 6 volts, check wiring between TP sensor connector terminal No. 3 and ECM connector terminal A16 for an open circuit.
  7. Turn ignition off. Reconnect TP sensor. Start and run engine at idle. Using Volvo Scan Tool (998-8686 ), read throttle angle. Throttle angle should be zero degrees when engine is at idle, increasing as accelerator is depressed. If reading is okay, source of DTC is poor contact at TP sensor connector. If reading is not okay, retest using new TPsensor.
  8. Turn ignition off. Connect TP sensor. Start and idle engine. Using Volvo Scan Tool (998-8686 ), read throttle angle. Throttle angle should be zero degrees when engine is at idle, increasing as accelerator is depressed. If reading is okay, TP sensor is okay. If reading is not okay, retest using new TP sensor.
  9. If fault is permanent and signal is too low, turn ignition off. Wait about 2 minutes. Disconnect TP sensor. Connect ohmmeter between TP sensor connector terminal No. 2 and ground. If ohmmeter reads .3-.8 k/ohm, go to step 11). If ohmmeter reads less than .3 k/ohm, check wiring between TP sensor connector terminal No. 2 and ECM connector terminal A15 for a short circuit to ground. If ohmmeter reads infinite resistance, go to next step.
  10. Turn ignition off. Disconnect TP sensor. Disconnect ECM connector. Ensure ECM connector terminals are clean and tight. Reconnect ECM connector. Turn ignition on. Connect voltmeter between TP sensor connector No. 2 and ground. If voltmeter reads about 6 volts, DTC is caused by poor contact at ECM connector terminals. If voltmeter does not read about 6 volts, check wiring between TP sensor connector terminal No. 2 and ECM connector terminal A15 for an open circuit.
  11. Turn ignition on. Disconnect TP sensor connector. Connect voltmeter between TP sensor connector terminal No. 3 and ground. If voltmeter reads about 6 volts, go to next step. If voltmeter does not read about 6 volts, check wiring between TP sensor connector terminal No. 3 and ECM connector terminal A16 for a short circuit to ground.
  12. Turn ignition off. Connect TP sensor. Start engine. Using Volvo Scan Tool (998-8686 ), read throttle angle. Throttle angle should be zero degrees at idle, and increase as accelerator pedal is depressed. If reading is okay, source of DTC is poor contact in TP sensor connector. If reading is not okay, retest using new TP sensor.
  13. If fault is intermittent and signal is too high, turn ignition off. Disconnect TP sensor. Turn ignition on. Connect voltmeter between TP sensor connector terminal No. 2 and ground. If voltmeter reads about 5 volts, go to next step. If voltmeter does not read about 5 volts, check wiring between TP sensor connector terminal No. 2 and ECM connector terminal A15 for a short circuit to voltage.
  14. Check TP sensor and ECM sensor connector terminals for loose connection, contact resistance, or oxidation. Check wiring between TP sensor connector terminal No. 3 and ECM connector terminal A16 for an intermittent open circuit or short circuit to voltage.
  15. If fault is intermittent and signal is too low, check TP sensor and ECM sensor connector terminals for loose connection, contact resistance, and oxidation. Check wiring between TP sensor connector terminal No. 3 and ECM connector terminal A16 for an intermittent short circuit to ground. Also check wiring between TP sensor connector terminal No. 1 and ECM connector terminal A18 for an intermittent open circuit or short circuit to ground.
scientia non olet · About LEMON Manuals