Theory Of Operation
| COMPONENT | LOCATION | CORRELATING PRESSURE SENSOR DTCS | CORRELATING TEMP SENSOR DTCS |
|---|---|---|---|
| BARO SENSOR | Inside the PCM | P0109, P2227, P2228, P2229, P3032 | N/A |
| Inlet Air Temperature (IAT) Sensor | Before the Throttle Body | N/A | P0111, P0112, P0113 |
| Supercharger Inlet MAP Sensor | Between the Throttle Body and Supercharger | P0069, P012A, P012B, P012C, P012D | P0096, P0097, P0098 |
| Supercharger Outlet MAP Sensor | On the Intake Manifold directly after the Supercharger | P00F8, P00F9, P00FA, P00FB | P00E9, P00EA, P00EB |
| Bank 1 MAP Sensor | Right side of the Intake Manifold | P0105, P0106, P0107, P0108 | P07B, P007C, P007D |
| Bank 2 MAP Sensor | Left side of the Intake Manifold | P2A0A, P2A0B, P2A0C, P2A0D | P00A1, P00A2, P00A3 |
| (1) Bank 1 TMAP Sensor | (3) Supercharger Inlet TMAP Sensor |
| (2) Supercharger Outlet TMAP Sensor | (4) Bank 2 TMAP Sensor |
| Inlet Air Temperature (IAT) not shown | |
The MAF Sensor was eliminated starting in model year 2017. It has been replaced by a standalone Intake Air Sensor that was previously part of the MAF Sensor.
The four TMAP Sensors also have an integral air temperature sensor. The temperature sensors have a 5.0 volt signal circuit and share the sensor ground circuit with the pressure sensor. They do not share the 5-Volt Reference circuit with the pressure sensor and therefore operate as a typical two wire temperature sensor.
The 6.2L engine uses several sensors to monitor the air pressure and temperature throughout the intake air system. The PCM uses this information to help calculate fuel delivery, ignition timing and Supercharger control. The PCM runs diagnostics to check the rationality of the sensors. The Supercharger Inlet Pressure Sensor is the centralized sensor in the system and is the main sensor used for the rationality diagnostics of the airflow before and after the Throttle Body.
Individual BARO/TMAP Sensor rationality diagnostic checks (P00F9, P012B, P0106, P2227, P2A0B):
- With the ignition on, engine not running, the BARO Sensor signal and four TMAP pressure signals are averaged. Each of the five sensor pressure signals is then compared to the average. If the BARO, or one of the TMAP Sensor pressure signals has a difference of more than a calibrated threshold from the average, a performance fault is set against that sensor.
- With the engine running, the input signals of the three TMAP Sensors that are downstream of the Supercharger (Supercharger Outlet TMAP Sensor, Bank 1 TMAP, Bank 2 TMAP) are compared. If the difference between one of the TMAP Sensor pressure signals and the other two pressure signals is more than a calibrated threshold a rationality fault will set. The calibrated threshold can vary between vehicles and models years but is generally between approximately 10.0 - 15.0 kPa (1.45 - 2.18 psi).
BARO/Supercharger Inlet TMAP Sensor rationality diagnostic check (P0069):
- The Supercharger Inlet TMAP Pressure signal is compared to the BARO signal to check rationality of the sensors. During natural aspiration, the Supercharger Inlet TMAP pressure signal cannot be greater than the BARO signal plus 10.3 kPa (1.49 psi). During boost conditions, the Supercharger Inlet TMAP pressure signal and BARO signal pressures should be similar. If the diagnostic fails during a drive cycle, a fault is set and the secondary Supercharger Inlet TMAP Pressure Sensor rationality diagnostic is run to determine which sensor is irrational.
Supercharger Inlet TMAP Pressure Sensor rationality diagnostic check (P012B):
- If either of the first two diagnostics fail during a given trip, or if one of the downstream TMAP Sensors is determined to be irrational, the PCM runs a secondary diagnostic to determine if the Supercharger Inlet TMAP Sensor is rational. With the engine in a natural aspiration condition (not boosted), the PCM compares the signal input from the Supercharger Inlet TMAP Sensor to the average of the Supercharger Outlet TMAP Sensor, Bank 1 TMAP, and Bank 2 TMAP Sensor signals. If the Supercharger Inlet TMAP Sensor is not within a calibrated threshold of the other three TMAP Sensors, it is determined to be irrational and a fault is set.
Temperature sensor rationality checks:
- After a cold soak of the engine, the Engine Coolant Temperature (ECT) and Ambient Air Temperature (AAT) Sensor inputs are compared to the inputs form each of the temperature sensors located in the TMAP Sensors. If a temperature sensor is not within a calibrated threshold of the ECT or AAT Sensors, a performance fault is set.