Circuit Description
The powertrain control module (PCM) supplies a 5-volt reference circuit and a low reference circuit to both the throttle position (TP) sensor and the manifold absolute pressure (MAP) sensor. The TP sensor sends a voltage signal back to the PCM relative to the throttle plate opening, and the MAP sensor sends a voltage signal back to the PCM relative to the intake manifold pressure. The PCM can detect if the TP sensor or the MAP sensor are out of range by comparing the two values against the high and low limits and engine speed defined within the engine calibration. If the TP or the MAP are not within the expected limits of the engine calibration, DTC P0105 is set.
Conditions for Running the DTC
DTCs P0107, P0108, P0117, P0118, P0122, P0123, P0125, P0128, P0130, P0131, P0132, P0171, P0172, P0201-P0204, P0300, P0301-P0304, P0336, P0440, P0442, P0446, P0452, P0453, P0506, P0507, P1441 are not set.
| • | The engine run time is more than 40 seconds. |
| • | The engine speed is between 900-6,375 RPM for a manual transmission. |
| OR |
| • | The engine speed is between 600-6,375 RPM for an automatic transmission. |
| • | The torque converter clutch (TCC) is stable to within 2.5 percent. |
| • | The engine speed is stable to within 50 RPM. |
| • | The idle air control (IAC) valve is stable to within 5 counts. |
| • | The above conditions are present for 1.5 seconds. |
Conditions for Setting the DTC
The MAP sensor or the TP sensor is out of an expected range defined by the engine calibration for 14 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
| • | If a DTC P0105 cannot be duplicated, the information included in the Freeze Frame/Failure Records can be useful. Use the scan tool DTC information data in order to determine the status of the DTC. |
| • | DTC P0105 may set due to any condition that may cause an unreasonably high or low map value including the following engine conditions: |
| - | Incorrect cam timing--Refer to Timing Chain and Sprocket Replacement in Engine Mechanical for the correct timing. |
| - | Restricted exhaust--Refer to Restricted Exhaust in Engine Exhaust. |
| - | Worn piston rings--Refer to Engine Compression Test in Engine Mechanical. |
| - | Low fuel pressure--Refer to Fuel System Diagnosis . |
| • | ATP sensor that is stuck may attempt to auto zero every time the engine runs. An indication if this happens is the TP percentage will be 0 percent and TP voltage will be high. |
| • | The MAP sensor needs a dedicated vacuum source. Check the MAP sensor and the MAP sensor vacuum source for a vacuum leak. |
| • | A short on any branch of the 5-volt reference circuit may cause this DTC to set. |
| • | Inspect for corroded terminals at the following connectors: |
| - | The MAP sensor |
| - | The TP sensor |
| - | PCM connector |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
While starting the engine, the MAP sensor should detect any changes in manifold pressure. This test is to determine if the sensor is stuck at a value.
-
A normal MAP sensor will react as quickly to the throttle changes as they can be made. A MAP sensor should not appear to be "lazy" or catch up with the throttle movements.
Step | Action | Values | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||||
2 |
Does the scan tool display a TP voltage less than the specified value when the throttle is fully closed? | 0.90 V | Go to Step 3 | Go to Step 4 | ||||||||
3 |
Does the throttle position (TP) angle increase steadily when the accelerator pedal is depressed to more than the first specified value and decrease steadily, returning to less than the second specified value when the pedal is released? | 98% 1% | Go to Step 5 | Go to Step 22 | ||||||||
4 | Check the throttle body for the following conditions:
Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 22 | ||||||||
5 |
Important: 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. Do you have access to another vehicle in which the manifold absolute pressure (MAP) sensor pressure can be observed with a scan tool? | -- | Go to Step 6 | Go to Step 7 | ||||||||
6 |
Is the difference between the values less than the specified value? | 3 kPa | Go to Step 8 | Go to Step 12 | ||||||||
7 |
Important: 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.
Does the MAP sensor indicate the correct barometric pressure? | -- | Go to Step 8 | Go to Step 12 | ||||||||
Start the engine while watching the MAP sensor value with the scan tool. Does the MAP sensor value change while starting the engine? | -- | Go to Step 9 | Go to Step 11 | |||||||||
With the engine running, snap the throttle while watching the MAP sensor display on the scan tool. Does the MAP sensor value change rapidly when the throttle position changes? | -- | Go to Step 10 | Go to Step 11 | |||||||||
10 |
Is the MAP sensor pressure within the specified range? | 19-42 kPa | Go to Diagnostic Aids | Go to Step 11 | ||||||||
11 |
Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 12 | ||||||||
12 |
Does the scan tool indicate that the voltage is near the specified value? | 0 V | Go to Step 13 | Go to Step 16 | ||||||||
13 | Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems. Is the voltage more than the specified value? | 5.2 V | Go to Step 18 | Go to Step 14 | ||||||||
14 |
Does the test lamp illuminate? | -- | Go to Step 15 | Go to Step 19 | ||||||||
15 |
Does the scan tool indicate that the MAP sensor voltage is near the specified value? | 5 V | Go to Step 17 | Go to Step 20 | ||||||||
16 | Test the MAP sensor signal circuit for a short to voltage. Refer Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 40 | ||||||||
17 |
Is the voltage more than the specified value? | 0.2 V | Go to Step 21 | Go to Step 35 | ||||||||
18 | Test all of the 5-volt reference circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 40 | ||||||||
19 | Test the 5-volt reference circuit of the MAP sensor for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 37 | ||||||||
20 | Test the MAP sensor signal circuit for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 37 | ||||||||
21 | Test the MAP sensor low reference circuit for high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 37 | ||||||||
22 |
Does the scan tool indicate that the TP sensor voltage is near the specified value? | 0 V | Go to Step 23 | Go to Step 26 | ||||||||
23 |
Does the test lamp illuminate? | -- | Go to Step 24 | Go to Step 28 | ||||||||
24 | Measure the voltage from the TP sensor 5-volt reference circuit to a good ground. Does the voltage measure more than the specified value? | 5.2 V | Go to Step 31 | Go to Step 25 | ||||||||
25 | Connect a 3-amp fused jumper between the TP sensor 5-volt reference circuit and the TP sensor signal circuit. Does the scan tool indicate that the TP sensor voltage is near the specified value? | 5 V | Go to Step 27 | Go to Step 32 | ||||||||
26 | Test the TP sensor signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 40 | ||||||||
27 |
Is the voltage more than the specified value? | 0.2 V | Go to Step 33 | Go to Step 36 | ||||||||
28 | Test the 5-volt reference circuit of the TP sensor for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 29 | ||||||||
29 | Test all of the branches of the 5-volt reference circuits that are shared with the TP sensor for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 30 | ||||||||
30 |
Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 37 | ||||||||
31 | Test the 5-volt reference circuit of the TP sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 34 | ||||||||
32 | Test the TP sensor signal circuit for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 37 | ||||||||
33 | Test the TP sensor low reference circuit for high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | 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. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 40 | ||||||||
35 | Inspect for poor connections at the MAP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 38 | ||||||||
36 | Inspect for poor connections at the TP sensor electrical connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 39 | ||||||||
37 | Inspect for poor connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 41 | Go to Step 40 | ||||||||
38 | Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement . Did you complete the replacement? | -- | Go to Step 41 | -- | ||||||||
39 | Replace the TP sensor. Refer to Throttle Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 41 | -- | ||||||||
40 | Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 42 | -- | ||||||||
41 | Use the scan tool in order to perform the Fuel Trim Reset procedure. Did you complete the procedure? | -- | Go to Step 42 | -- | ||||||||
42 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 43 | ||||||||
43 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |||||||||
