LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Saturn >> 2003 >> L200 Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0105: Map Sensor Circuit Range/Performance >> Diagnostic Procedures
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedures

  1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition on, with engine off. Monitor the DTC information with a scan tool. Is DTC P0452, P0453, or P0530 also set? If yes, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go to next step.
  3. Turn ignition on, with engine off. Observe the Throttle Position (TP) sensor voltage with a scan tool. Is the voltage less than 0.85 volt when throttle is fully closed? If yes, go to next step. If no, go to step  5.
  4. Observe the TP sensor angle with a scan tool. Monitor the scan tool while slowly depressing the accelerator pedal to the floor, slowly releasing the pedal. Repeat the procedure several times. Does the TP angle increase steadily when the accelerator pedal is depressed to more than 98 percent and decrease steadily, returning to less than 1 percent, when pedal is released? If yes, go to step  6. If no, go to step  18.
  5. Inspect the throttle body for binding or damaged throttle cable, damaged throttle blade, or binding or damaged cruise control cable. Did you find and correct the condition? If yes, go to step  34. If no, go to step  18.
    6. NOTE: The vehicle used for the comparison is not limited to the same type of vehicle as is being serviced. A vehicle known to provide an accurate reading is acceptable.
  6. Do you have access to another vehicle in which the MAP sensor pressure can be observed with a scan tool? If yes, go to next step. If no, go to step  8.
  7. Turn ignition on, with engine off. Observe the MAP sensor pressure with a scan tool. Observe the MAP sensor pressure in the known good vehicle with a scan tool. Compare the values. Is the difference between the values less than 3 kPa? If yes, go to step  9. If no, go to step  14.
    8. NOTE: The Altitude vs Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or very low or very high temperature may cause a reading to be slightly out of range.
  8. Turn ignition on, with engine off. Observe the MAP sensor pressure with a scan tool. ALTITUDE VS. BAROMETRIC PRESSURE  table. The MAP sensor pressure should be within the range specified for your altitude. Does the MAP sensor indicate the correct barometric pressure? If yes, go to next step. If no, go to step  14.
  9. Start engine while observing the MAP sensor value with the scan tool. Does the MAP sensor value change while starting the engine? If yes, go to next step. If no, go to step  13.
  10. With the engine running, snap the throttle while observing the MAP sensor value on the scan tool. Does the MAP sensor value change rapidly when the throttle position changes? If yes, go to next step. If no, go to step  13.
  11. Allow engine to reach operating temperature. Ensure that transaxle is in Park or Neutral. Turn OFF all of the accessories. Allow engine to idle. Observe the MAP sensor pressure with a scan tool. Is the MAP sensor pressure within 19-42 kPa? If yes, go to DIAGNOSTIC AIDS . If no, go to next step.
  12. Test for engine vacuum leaks, restricted exhaust, worn piston rings, or incorrect cam timing for correct timing. Did you find and correct the condition? If yes, go to step  34. If no, go to step  14.
  13. Turn ignition off. Remove the MAP sensor from the vacuum source. Inspect the port for vacuum restrictions or vacuum leaks. Did you find and correct the condition? If yes, go to step  34. If no, go to next step.
  14. Turn ignition off. Disconnect the MAP sensor electrical connector. Turn ignition on. Observe the MAP sensor voltage with a scan tool. Is the voltage less than 0.2 volt? If yes, go to next step. If no, go to step  21.
  15. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DVOM. Note the measurement as supply voltage. Connect a test light and a DVOM in series between the 5-volt reference circuit and the low reference circuit of the MAP sensor at the harness connector. Measure the amperage with the DVOM. Note the measurement as Amperage. Is the amperage at zero mA? If yes, go to step  23. If no, go to next step.
  16. Remove the DVOM from the circuit. Connect the test light between the 5-volt reference circuit and the low reference circuit of the MAP sensor at the harness connector. Measure the voltage from the 5-volt reference circuit at the test light to a good ground with the DVOM. Note the measurement as Load voltage drop. Subtract the Load voltage drop from the Supply voltage. Note the result as Supply voltage drop. Divide the Supply voltage drop by the amperage. Is the result more than 5 ohms? If yes, go to step  22. If no, go to next step.
  17. Measure the voltage from the low reference circuit of the MAP sensor at the test light to a good ground with the DVOM. Note the result as Low reference voltage drop. Divide the low reference voltage drop by the amperage. Is the result more than 5 ohms? If yes, go to step  24. If no, go to step  28.
  18. Disconnect the TP sensor. Measure the voltage from the 5-volt reference circuit of the TP sensor to a good ground with a DVOM. Note the measurement as Supply voltage. Is the voltage more than 5.2 ohms? If yes, go to step  25. If no, go to next step.
  19. Connect a test light and a DVOM in series between the 5-volt reference circuit and the low reference circuit of the TP sensor at the harness connector. Measure the amperage with the DVOM. Note the measurement as Amperage. Remove the DVOM from the circuit. Connect the test light between the 5-volt reference circuit and the low reference circuit of the TP sensor at the harness connector. Measure the voltage from the 5-volt reference circuit at the test light to a good ground with the DVOM. Note the measurement as Load voltage drop. Subtract the Load voltage drop from the Supply voltage. Note the result as Supply voltage drop. Divide the Supply voltage drop by the amperage. Is the result more than 5 ohms? If yes, go to step  26. If no, go to next step.
  20. Measure the voltage from the low reference circuit of the TP sensor at the test light to a good ground with the DVOM. Note the result as Low reference voltage drop. Divide the low reference voltage drop by the amperage. Is the result more than 5 ohms? If yes, go to step  27. If no, go to step  29.
  21. Test the MAP sensor signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  34. If no, go to step  33.
  22. Test the 5-volt reference circuit of the MAP sensor for high resistance. Did you find and correct the condition? If yes, go to step  34. If no, go to step  30.
  23. Test the MAP sensor low reference circuit for an open. Did you find and correct the condition? If yes, go to step  34. If no, go to step  30.
  24. Test the MAP sensor low reference circuit for high resistance. Did you find and correct the condition? If yes, go to step  34. If no, go to step  30.
  25. Test the 5-volt reference circuit of the TP sensor for a short to voltage. Did you find and correct the condition? If yes, go to step  34. If no, go to step  33.
  26. Test the 5-volt reference circuit of the TP sensor for high resistance. Did you find and correct the condition? If yes, go to step  34. If no, go to step  30.
  27. Test the low reference circuit of the TP sensor for high resistance. Did you find and correct the condition? If yes, go to step  34 If no, go to step  30.
  28. Test for poor connections at the MAP sensor. Did you find and correct the condition? If yes, go to step  34. If no, go to step  31.
  29. Test for poor connections at the TP sensor electrical connector. Did you find and correct the condition? If yes, go to step  34. If no, go to step  32.
  30. Test for poor connections at the PCM. Did you find and correct the condition? If yes, go to step  34. If no, go to step  33.
  31. Replace MAP sensor. After replacement, go to step  34.
  32. Replace TP sensor. After replacement, go to step  34.
  33. Replace PCM. See POWERTRAIN CONTROL MODULE in REMOVAL & INSTALLATION - SATURN "L" SERIES article. Perform PCM relearn procedure. See PCM REPROGRAMMING  under PROGRAMMING. After replacing PCM, go to next step.
  34. Clear the DTCs with a scan tool. Turn ignition off for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. See CONDITIONS FOR RUNNING DTC . You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition? If yes, go to step  2. If no, go to next step.
  35. Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? If yes, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
scientia non olet · About LEMON Manuals