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| • | 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 provide an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
FTP Sensor 5 V Reference | P0452, P0532, P0641 | P0452 | P0453, P0533,P0641 * | - |
FTP Sensor Signal | P0452 | P0452 | P0453 * | - |
FTP Sensor Low Reference | - | P0453, P0463, P1458, P145A | - | - |
* Internal ECM or FTP sensor damage may occur if the circuit is shorted to B+. | ||||
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Vehicle in Service Mode Parameter Normal Range: 0.15-4.85 V | |||
FTP Sensor 5 V Reference | 0 V | 0-1.5 V | 5 V |
FTP Sensor Signal | 0 V | 0 V | 3-5 V |
FTP Sensor Low Reference | - | 4-5 V | - |
The fuel tank pressure (FTP) sensor measures the pressure or vacuum in the evaporative emission (EVAP) system. The engine control module (ECM) supplies a 5 V reference and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies depending on EVAP system pressure or vacuum.
The following tables illustrate relationship examples between the FTP sensor and the ON and OFF states, and the OPEN or CLOSED states of the EVAP components:
Fuel Tank Pressure | FTP in. H2O/PSI | FTP Signal Voltage |
|---|---|---|
Pressure | Positive Value, 14.9 in. H2O / 0.54 PSI | High, 4.73 V |
No Pressure | Near Zero, 0 in. H2O / 0.001 PSI | 2.6 V |
Vacuum | Negative Value, -2.37 in. H2O / -0.08 PSI | Low, 2.3 V |
Fuel Tank Pressure | FTP Sensor | EVAP Leak Detection Pump Switch Valve | Vent Valve | EVAP Leak Detection Pump Pressure |
|---|---|---|---|---|
Pressure or Vacuum | Positive or Negative Value | Vent | Closed | 100 kPa (14.50 PSI) * |
Vacuum | Negative Value - 1 kPa (0.15 PSI) | Pump/Not Venting | Open | 99 kPa (14.36 PSI) ** |
Pressure | Positive Value - 3 kPa (0.44 PSI) | Pump/Not Venting | Open | 103 kPa (14.94 PSI) ** |
* Equivalent to barometric pressure reading. ** The values are examples only. Your readings may vary from this depending on the pressure or vacuum in the system and barometric pressure. | ||||
| • | DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P012B, P012C, P012D, P0222, P0223, P0449, P0452, P0453, P0461, P0462, P0463, P0498, P0499, P0502, P0503, P06E4, P06E4, P0722, P0723, P1221, P1459, P145A, P2066, P2067, P2068, P2400, P2401, P2402, P2418, P2419, P2420, U0140, U182D, U0073, U0074, P2537 or P2610 is not set. |
| • | DTC P1458 or P145D are not present when the test failed this ignition cycle. |
| • | The barometric pressure (BARO) is between 70-110 kPa (10 -16 PSI). |
| • | The fuel level is between 10-90 %. |
| • | The engine coolant temperature (ECT) is less than 40°C (104°F). |
| • | The inlet air temperature (IAT) is between 4°-45°C (39°-113°F). |
| • | The propulsion system is not active. |
| • | The vehicle is OFF. |
| • | The service bay test is not active. |
| • | The refuelling request button is not pressed. |
| • | The battery voltage is greater than 10 V. |
| • | The vehicle speed is less than 1.6 km/h (1 MPH). |
| • | There are three possible time windows for this test to run. Up to that point and through this time period the propulsion system must not be active. These time windows are: 5.0, 7.0 or 9.5 hours. |
| • | The DTC runs once per drive cycle and immediately after a code clear when the above conditions are met. |
| • | DTCs P0068, P0071, P0072, P0073, P010C, P010D, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P012B, P012C, P012D, P0121, P0122, P0123, P0222, P0223, P0442, P0443, P0449, P0452, P0453, P0455, P0458, P0459, P0498, P0499, P0502, P0503, P0722, P0723, P0606, P1104, P1221, P145A, P145D, P145E, P1458, P1459, P16F3, P2100, P2101, P2102, P2103, P2400, P2401, P2402, P2418, P2419, P2420, P2422 or P2450 is not set. |
| • | The barometric pressure (BARO) is between 70-110 kPa (10-16 PSI). |
| • | The outside air temperature (OAT) is between 4°-35°C (39-102°F). |
| • | The engine is running. |
| • | The run/crank voltage is greater than 11 V. |
| • | The EVAP Purge solenoid valve is not enabled. |
| • | The refueling request button is not pressed |
| • | The DTC runs once per drive cycle when the above conditions are met. |
| • | Vehicle ON or the engine is running. |
| • | DTCs P0452 and P0453 run continually when the above conditions are met. |
The ECM detects the difference between the FTP sensor and the EVAP leak detection pump (ELDP) pressure is greater than 0.747 kPa (0.11 PSI) for greater than 5 s
The ECM detects the FTP sensor voltage is less than 0.15 V for greater than 8 s.
The ECM detects the FTP sensor voltage is greater than 4.85 V for greater than 8 s.
DTCs P0451, P0452 and P0453 are Type B DTCs.
DTCs P0451, P0452 and P0453 are Type B DTCs.
| • | A restriction in the EVAP canister or vent lines that keeps the FTP and EVAP leak detection pump sensor from comparing each others value. |
| • | Since this is a sealed system there could be a pressure or vacuum existing in the system. |
| • | A vent valve stuck closed will affect performance. |
| • | A switching valve stuck in the vent position will affect performance. |
| • | Ensure that the reference port on the FTP sensor is unobstructed. |
| • | Scan tool output controls, snapshot, and the plot function can help detect erratic sensor operation. |
Evaporative Emission Control System Description
Hybrid Modes of Operation Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
J 41413-200 Evaporative Emissions System Tester
For equivalent regional tools, refer to Special Tools : Diagnostic Tools .
Note: The order of these steps is important. If not followed properly you will be bleeding off any pressure or vacuum in the system and not see any change in the EVAP leak detection pump sensor.
| ⇒ | If the FTP is 0 in. H2O (0 PSI), 0.15-0.29 PSI pressure or vacuum will need to added to the EVAP system. |
| ⇒ | If the FTP is 15 in. H2O (0.54 PSI), you will need to reduce the pressure or vacuum by 0.15-0.29 PSI before proceeding as this is outside the readable range of the FTP sensor. |
Note: Ambient and vehicle component temperature must be above 0°C (32°F) to command the switching valve. This prevents erroneous results and damage to the EVAP leak detection pump assembly.
Note: Testing for steps 2-6 is performed on the ECM side of the harness connector.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 engine control module. |
| ⇒ | If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 engine control module. |
| ⇒ | If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 engine control module. |
| ⇒ | If greater than the specified range, test the B150 fuel tank pressure sensor circuit terminal 1 for a short to voltage. If the circuit tests normal, replace the K20 engine control module. |
| ⇒ | If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 engine control module. |
Note: Testing for this step is performed on the EVAP assembly side of the harness connector.
| • | Poor connection at the X350 harness connector |
| • | Open or shorted 5 V reference circuit |
| • | Open or shorted sensor signal circuit |
| • | Open low reference circuit |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming. |
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