LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2002 >> Eldorado ECS >> Repair and Diagnosis >> External Pages >> Different car >> Section 249 (Engine Controls Self-Diagnostics - 2.2L) >> Diagnostic Tests >> DTC P0105: Map/TP Sensor Circuit - Insufficient Activity >> Diagnostic Procedures
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedures

WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
  2. Install scan tool. Turn ignition on, with engine off. Observe the TP sensor voltage on the scan tool. Does scan tool display a TP voltage less than 0.90 volt when the throttle is fully closed? If yes, go to next step. If no, go to step  4 .
  3. Select the TP angle parameter on the scan tool. Monitor the scan tool while slowly depressing the accelerator pedal to the floor, then slowly release the pedal. Repeat the procedure several times. Does the TP angle value increase steadily when accelerator pedal is depressed to more than 98 percent and decrease steadily, returning to less than one percent when pedal is released? If yes, go to step  5 . If no, go to step  24 .
  4. Check throttle body for binding or damaged linkage. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  22 .
    5. NOTE: The vehicle used for comparison is not limited to the same type of vehicle being serviced. A vehicle known to provide an accurate reading is acceptable.
  5. 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  7 .
  6. Turn ignition on, with engine off. Observe MAP sensor pressure with scan tool. Observe MAP sensor pressure in the known-good vehicle with scan tool. Compare the values. Is the difference between the values less than 3 kPa? If yes, go to step  8 . If no, go to step  12 .
    7. NOTE: The Altitude vs Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Refer to SENSOR OPERATING RANGE CHARTS - TRUCKS article. 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.
  7. Turn ignition on, with engine off. Observe MAP sensor pressure with scan tool. MAP sensor pressure should be within the range specified for your altitude. Refer to SENSOR OPERATING RANGE CHARTS - TRUCKS article. Does the MAP sensor indicate the correct barometric pressure? If yes, go to next step. If no, go to step  12 .
  8. Start engine while watching the MAP sensor value with scan tool. Does the MAP sensor value change while starting the engine? If yes, go to next step. If no, go to step  11 .
  9. With engine running, snap the throttle while watching the MAP sensor display on 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  11 .
  10. Allow engine to reach operating temperature. Ensure that transaxle is in Park or Neutral. Turn off all accessories. Allow engine to operate at idle. Observe MAP sensor pressure with scan tool. Is MAP sensor pressure within 19-42 kPa? If yes, see DIAGNOSTIC AIDS  . If no, go to next step.
  11. Turn ignition off. Remove MAP sensor from vacuum source. Inspect port for vacuum restrictions or vacuum leaks. Did you find and correct the condition? If yes, go to step  41 . If no, go to next step.
  12. Turn ignition off. Disconnect MAP sensor electrical connector. Turn ignition on. Observe MAP sensor voltage on scan tool. Does scan tool indicate that voltage is about zero volts? If yes, go to next step. If no, go to step  16 .
  13. Measure voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DVOM. Is voltage more than 5.2 volts? If yes, go to step  18 . If no, go to next step.
  14. Connect a test light to a good ground. Probe the 5-volt reference circuit of the MAP sensor with test light. Does test light illuminate? If yes, go to next step. If no, go to step  19 .
  15. Connect a 3-amp fused jumper to the MAP sensor 5-volt reference circuit. Connect the other end of the 3-amp fused jumper to the MAP sensor signal circuit. Does the scan tool indicate that the MAP sensor voltage is about 5 volts? If yes, go to step  17 . If no, go to step  20 .
  16. Test the MAP sensor signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  40 .
  17. Remove jumper wire. Connect a jumper wire between each of the terminals in the MAP sensor harness connector and corresponding terminal at the MAP sensor. Turn ignition on, with engine off. Measure voltage from the low reference circuit of the MAP sensor, at the jumper wire terminal, to a good ground with DVOM. Is voltage more than 0.2 volt? If yes, go to step  21 . If no, go to step  35 .
  18. Test all of the 5-volt reference circuits for a short to voltage. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  40 .
  19. Test the 5-volt reference circuit of the MAP sensor for an open, high resistance or short to ground. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  37 .
  20. Test MAP sensor signal circuit for an open, short to ground or high resistance. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  37 .
  21. Test MAP sensor low reference circuit for high resistance or an open. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  37 .
  22. Turn ignition off. Disconnect TP sensor electrical connector. Turn ignition on. Observe the TP sensor voltage on scan tool. Does scan tool indicate that the TP sensor voltage is about zero volts? If yes, go to next step. If no, go to step  26 .
  23. Connect a test light to a good ground. Probe the 5-volt reference circuit of the TP sensor with test light. Does the test light illuminate? If yes, go to next step. If no, go to step  28 .
  24. Measure voltage from the TP sensor 5-volt reference circuit to a good ground. Does the voltage measure more than 5.2 volts? If yes, go to step  31 . If no, go to next step.
  25. Connect a 3-amp fused jumper between the TP sensor 5-volt reference circuit and TP sensor signal circuit. Does scan tool indicate that the TP sensor voltage is about 5 volts? If yes, go to step  27 . If no, go to step  32 .
  26. Test the TP sensor signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  40 .
  27. Remove jumper wire. Connect a jumper wire between each of the terminals in the TP sensor harness connector and corresponding terminal at TP sensor. Turn ignition on, with engine off. Measure voltage from the low reference circuit of the TP sensor, at the jumper wire terminal, to a good ground with a DVOM. Is voltage more than 0.2 volt? If yes, go to step  33 . If no, go to step  36 .
  28. Test the 5-volt reference circuit of the TP sensor for an open, short to ground or high resistance. Did you find and correct the condition? If yes, go to step  41 . If no, go to next step.
  29. Test all of the branches of the 5-volt reference circuits that are shared with the TP sensor for a short to ground. Did you find and correct the condition? If yes, go to step  41 . If no, go to next step.
  30. Measure the voltage from the 5-volt reference circuit of the TP sensor to the low reference circuit of the TP sensor. Disconnect all of the other sensors that share the 5-volt reference circuit with the TP sensor, one at a time. A change in voltage indicates the faulty component. Replace affected component as necessary. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  37 .
  31. 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  41 . If no, go to step  34 .
  32. Test the TP sensor signal circuit for an open, a short to ground or high resistance. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  37 .
  33. Test the TP sensor low reference circuit for high resistance or an open. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  37 .
  34. Test all of the 5-volt reference circuits that are shared with the TP sensor for a short to voltage. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  40 .
  35. Inspect for poor connections at MAP sensor. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  38 .
  36. Inspect for poor connections at the TP sensor electrical connector. Did you find and correct the condition? If no, go to step  41 . If no, go to step  39 .
  37. Check connections at PCM. Did you find and correct the condition? If yes, go to step  41 . If no, go to step  40 .
  38. Replace MAP sensor. After replacing sensor, go to step  41 .
  39. Replace TP sensor. After replacing sensor, go to step  41 .
  40. Replace PCM. See appropriate REMOVAL & INSTALLATION article. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  41. Use scan tool in order to perform the Fuel Trim Reset procedure. Did you complete the procedure? If yes, go to next step.
  42. Clear DTCs with scan tool. Turn ignition off for 30 seconds. Start engine. Operate the vehicle within the Conditions for Running this DTC. See CONDITIONS FOR RUNNING DTC  . Does the scan tool indicate that this diagnostic ran and passed? If yes, go to next step. If no, go to step  2 .
  43. With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no, system is okay.
scientia non olet · About LEMON Manuals