• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
5-Volt Reference | P0107, P0452, P0532, P0641 | P0106, P0107 | P0107 | P0106, P0108, P0453, P0533, P0641 | P0106, P1101 |
Manifold Absolute Pressure Sensor Signal | P0107 | P0106, P0107 | P0107 | P0108 | P0106, P1101 |
Low Reference | -- | P0106, P0108 | P0106, P0108 | -- | P0106, P1101 |
Circuit | Short to Ground | Open or High Resistance | Short to Voltage |
---|---|---|---|
Operating Conditions: The ignition is ON or the engine is running Parameter Normal Range: 12-103 kPa | |||
5-Volt Reference | 10 kPa | 10 kPa | 104 kPa |
Manifold Absolute Pressure Sensor Signal | 10 kPa | 10 kPa | 104 kPa |
Low Reference | -- | 90-104¹ kPa | -- |
¹Variation according to the ECM version |
Circuit | Short to Ground | Open or High Resistance | Short to Voltage |
---|---|---|---|
Operating Conditions: The ignition is ON or the engine is operating Parameter Normal Range: 4.7-5 volts | |||
5-Volt Reference | 0 V | 0 V | 4.98 V |
Manifold Absolute Pressure Sensor Signal | 0 V | 0 V | 4.98 V |
Low Reference | -- | 4.5-4.98¹ V | -- |
¹Variation according to the ECM version |
The intake flow rationality diagnosis provides the within-range rationality check for the mass air flow (MAF), manifold absolute pressure (MAP), and the throttle position (TP) sensors. This is an displayed model based diagnosis containing 4 separate models for the intake system.
• | The throttle model describes the flow through the throttle body and is used to estimate the MAF through the throttle body as a function of barometric pressure (BARO), TP, intake air temperature (IAT), and estimated MAP. The information of this model is displayed on the scan tool as the MAF performance test parameter. |
• | The first intake manifold model describes the intake manifold and is used to estimate MAP as a function of the MAF into the manifold from the throttle body and the MAF out of the manifold caused by engine. The flow into the manifold from the throttle uses the MAF estimate calculated from the above intake manifold model. The information of this model is displayed on the scan tool as the MAP performance test 1 parameter. |
• | The only difference between the second intake manifold model and the first intake manifold model is that the second one uses MAF sensor measurement, not the throttle air flow estimated by the throttle model. The information of this model is displayed on the scan tool as the MAP performance test 2 parameter. |
• | The fourth model is created from the combination and additional calculations of the throttle model and the first intake manifold model. The information of this model is displayed on the scan tool as the TP performance test parameter. |
Then, the estimates of MAF and MAP calculated from this system of models and calculations are then compared with the actual measured values from the MAF, MAP, and the TP sensors and to each other to determine the appropriate DTC failing. The following table illustrates the possible failure combinations and the resulting DTC or DTCs.
MAF Performance Test | MAP Performance Test 1 | MAP Performance Test 2 | TP Performance Test | DTCs Passed | DTCs Failed |
---|---|---|---|---|---|
X | X | OK | OK | P0101, P0106, P0121, P1101 | None |
OK | OK | Fault | OK | P0101, P0106, P0121, P1101 | None |
Fault | OK | Fault | OK | P0106, P0121, P1101 | P0101 |
OK | Fault | Fault | OK | P0101, P0121, P1101 | P0106 |
Fault | Fault | Fault | OK | P0121, P1101 | P0101, P0106 |
X | X | OK | Fault | P0101, P0106, P1101 | P0121 |
OK | OK | Fault | Fault | P0101, P0106, P0121, P1101 | None |
Fault | OK | Fault | Fault | P0101, P0106, P0121 | P1101 |
X | Fault | Fault | Fault | P0101, P0106, P0121 | P1101 |
• | DTCs P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0128, P0335, P0336, P0401, P0405, P1404 are not set. |
• | The engine speed is between 550-5,000 RPM. |
• | The IAT sensor parameter at -7 to +60°C (+19 to +140°F). |
• | The ECT sensor parameter at 70-129°C (158-264°F). |
• | The DTCs run continuously when the conditions are met. |
The engine control module (ECM) detects that the MAP sensor pressure is not within range of the calculated pressure that is derived from the system of models.
DTC P0106 is a Type B DTC.
DTC P0106 is a Type B DTC.
• | A skewed or invariable engine coolant temperature (ECT) or IAT will cause the calculated models inaccurate and may cause the DTC to run when it should not. Refer to Temperature Versus Resistance. |
• | The BARO that is used by the ECM to calculate the air flow models is initially based on the MAP sensor value at ignition ON. When the engine is running, the ECM will continually update the BARO value near wide open throttle (WOT) using the MAP sensor and a calculation. A skewed MAP sensor will cause the BARO value to be inaccurate. Use a scan tool and compare the BARO parameter with the ignition ON according to the Altitude vs. Barometric Pressure table. Refer to Altitude Versus Barometric Pressure. |
• | A skewed MAP sensor value will also cause the first and second intake manifold models calculated to disagree with the actual MAP sensor measurements. Use a scan tool and compare the MAP sensor parameter with a known good vehicle parameter under various operating conditions. |
Diagnostic Trouble Code (DTC) Type Definitions
J 35555 Metal Mityvac
• | Damaged components |
• | Loose or improper installation |
• | Restricted air flow |
• | A cracked or restricted MAP sensor vacuum hose |
• | Intake manifold leak |
Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
⇒ | If greater than the specified range, test the low reference circuit for an open or high resistance. If the circuit test normal, replace the ECM. |
⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground, open, or high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If greater than the specified range, test the 5-volt reference circuit for short to voltage. If the circuit test normal, replace the ECM. |
⇒ | If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit test normal, replace the ECM. |
⇒ | If less than the specified range, test the signal circuit for a short to ground, or an open or high resistance. If the circuit tests normal, replace the ECM. |
Note: You must perform the Circuit/System Testing before proceeding with Component Testing.
⇒ | If the voltage is not within the specified range or is unstable, replace the MAP sensor. |
• | Control Module References for ECM replacement, setup, and programming |