Circuit Description
The manifold absolute pressure (MAP) sensor responds to pressure changes in the intake manifold. The pressure changes occur based on the engine load. The engine control module (ECM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The ECM also provides a ground on the low reference circuit. The MAP sensor provides a signal to the ECM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The ECM should detect a low signal voltage at a low MAP, such as during an idle or a deceleration. The ECM should detect a high signal voltage at a high MAP, such as the ignition is ON, with the engine OFF, or at a wide open throttle (WOT). The MAP sensor is also used to determine the barometric pressure (BARO). This occurs when the ignition switch is turned ON, with the engine OFF. The BARO reading may also be updated whenever the TP sensor is more than 28 percent. The MAP sensor contains the following circuits:
| • | A 5-volt reference |
| • | A low reference |
| • | A MAP sensor signal |
If the ECM detects the MAP sensor signal is not within the predicted range this DTC sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0106 Manifold Absolute Pressure (MAP) Sensor Performance
Condition for Running the DTC
| • | The altitude compensated MAP reading is higher than high threshold or lower than low threshold table based on RPM and the TP signal. |
| • | DTCs P0107, P0108, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0300, P0351, P0352, P0401, P0402, P0404, P0405, P0406, P0506, P0507, and P1404 are not set. |
| • | The engine is running. |
| • | Valid barometric pressure (BARO) update |
| • | The torque converter clutch (TCC) is at a steady state. |
| • | Air conditioning (A/C) steady state |
| • | The engine speed is between 1,300-4,500 RPM. |
| • | The change in engine speed is less than 200 RPM. |
| • | Change in the idle air control (IAC) is less than 5 percent. |
| • | The coolant temperature is greater than -10°C (+14°F). |
| • | The change in throttle position (TP) is less than 3 percent, or the change in MAP is less than 5 percent. |
| • | The change in the exhaust gas recirculation (EGR) value is less than 6 percent. |
| • | All of the above are stabilized for 1.5 seconds. |
| • | DTC P0106 runs continuously once the above conditions are met. |
Conditions for Setting the DTC
The ECM detects that the actual MAP signal is not within the predicted range for more than 25 seconds.
Action Taken When the DTC Sets
| • | The malfunction indicator lamp (MIL) will illuminate after 3 consecutive ignition cycles with a fail. |
| • | The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame/Failure Records buffers. |
| • | A history DTC is stored. |
| • | The ECM will substitute a fixed MAP value and use the TP sensor to control the fuel delivery. The scan tool will not show defaulted value. |
Conditions for Clearing the MIL/DTC
| • | The MIL will turn OFF after 4 consecutive ignition cycles in which the diagnostic runs without a fault. |
| • | A history DTC will clear after 40 consecutive warm-up cycles without a fault. |
| • | DTCs can be cleared by using the scan tool. |
| • | Disconnect the ECM battery feed for more than 10 seconds. |
Diagnostic Aids
With the ignition ON and the engine stopped, the manifold pressure is equal to atmospheric pressure and the signal voltage will be high. This information is used by the ECM as an indication of vehicle altitude. Comparison of this reading with a known good vehicle with the same sensor is a good way to check the accuracy of a suspected sensor. Reading should be the same +0.4 volt.
The MAP sensor vacuum source should be thoroughly inspected for restrictions at the intake manifold.
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. A MAP sensor should not appear to be "lazy" or catch up with the throttle movements.
Step | Action | Value | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View References: Engine Controls Connector End Views | ||||||||||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |||||||||
2 |
Is the voltage less than the specified value when the throttle is fully closed? | 0.4 V | Go to Step 3 | Go to Step 4 | ||||||||
3 |
Does the 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? | 85% 15% | Go to Step 5 | Go to Step 18 | ||||||||
4 | Inspect the throttle body for the following conditions:
Did you find and correct the condition? | -- | Go to Step 38 | Go to Step 18 | ||||||||
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 13 | ||||||||
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 13 | ||||||||
Start the engine while observing the MAP sensor pressure parameter with the scan tool. Does the MAP sensor pressure parameter change while starting the engine? | -- | Go to Step 9 | Go to Step 12 | |||||||||
With the engine running, snap the throttle while observing the MAP sensor pressure parameter on the scan tool. Does the MAP sensor pressure parameter change rapidly when the throttle position changes? | -- | Go to Step 10 | Go to Step 12 | |||||||||
10 |
Is the MAP sensor pressure within the specified range? | 12-96 kPa | Go to Intermittent Conditions | Go to Step 11 | ||||||||
11 | Test for the following conditions:
Did you find and correct the condition? | -- | Go to Step 38 | Go to Step 13 | ||||||||
12 |
Did you find and correct the condition? | -- | Go to Step 38 | Go to Step 13 | ||||||||
13 |
Is the pressure less than the specified value? | 12 kPa | Go to Step 14 | Go to Step 23 | ||||||||
14 | 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 24 | Go to Step 15 | ||||||||
15 | Probe the 5-volt reference circuit of the MAP sensor with a test lamp that is connected to a good ground. Is the test lamp OFF? | -- | Go to Step 25 | Go to Step 16 | ||||||||
16 |
Is the pressure more than the specified value? | 12 kPa | Go to Step 17 | Go to Step 26 | ||||||||
17 |
Is the voltage more than the specified value? | 0.2 V | Go to Step 27 | Go to Step 32 | ||||||||
18 |
Is the voltage less than the specified value? | 0.2 V | Go to Step 19 | Go to Step 28 | ||||||||
19 | Measure the voltage from the TP sensor 5-volt reference circuit to a good ground. Is the voltage more than the specified value? | 5.2 V | Go to Step 24 | Go to Step 20 | ||||||||
20 | Probe the 5-volt reference circuit of the TP sensor with a test lamp that is connected to a good ground. Is the test lamp OFF? | -- | Go to Step 29 | Go to Step 21 | ||||||||
21 |
Is the TP sensor angle more than the specified value? | 0% | Go to Step 22 | Go to Step 30 | ||||||||
22 |
Is the voltage more than the specified value? | 0.2 V | Go to Step 31 | Go to Step 33 | ||||||||
23 | Test the MAP 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 38 | Go to Step 37 | ||||||||
24 | 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 38 | Go to Step 37 | ||||||||
25 | Test the 5-volt reference circuit of the MAP sensor for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 38 | Go to Step 34 | ||||||||
26 | 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 38 | Go to Step 34 | ||||||||
27 | 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 38 | Go to Step 34 | ||||||||
28 | 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 38 | Go to Step 37 | ||||||||
29 | Test the 5-volt reference circuit of the TP sensor for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 38 | Go to Step 34 | ||||||||
30 | 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 38 | Go to Step 34 | ||||||||
31 | Test the low reference circuit of the TP sensor 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 38 | Go to Step 34 | ||||||||
32 | Test for an intermittent and for a poor connection 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 38 | Go to Step 35 | ||||||||
33 | Test for an intermittent and for a poor connection at the TP 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 38 | Go to Step 36 | ||||||||
34 | Test for an intermittent and for a poor connection at the engine control module (ECM). 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 38 | Go to Step 37 | ||||||||
35 | Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement . Did you complete the replacement? | -- | Go to Step 38 | -- | ||||||||
36 | Replace the TP sensor. Refer to Throttle Position Sensor Replacement . Did you complete the replacement? | -- | Go to Step 38 | -- | ||||||||
37 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 38 | -- | ||||||||
38 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 39 | ||||||||
39 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |||||||||
