Test Description
WARNING: This page is about a different car, the 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers on the diagnostic table.
- 4: The ECM produces a measurable steady state amperage that provides the 5-volt reference to the FTP sensor. If the amperage on the 5-volt reference circuit is less than 80 mA, test the 5-volt reference circuit for an open or high resistance.
- 5: This step tests the signal circuit of the FTP sensor.
P0452 Fuel Tank Pressure (FTP) Sensor Circuit Low Voltage
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views |
||||
| 1 | Did you perform the Diagnostic System Check-Engine Controls? | - | Go to Step 2 | Go to Diagnostic System Check - Engine Controls |
| 2 |
|
0.13 V | Go to Step 4 | Go to Step 3 |
| 3 |
|
- | Go to Step 4 | Go to Diagnostic Aids |
| 4 |
|
80 mA | Go to Step 5 | Go to Step 7 |
| 5 |
|
4.8 V | Go to Step 8 | Go to Step 6 |
| 6 | Test the signal circuit of the FTP sensor for an open, or a short to ground between the fuel tank harness connector and the ECM. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 14 | Go to Step 11 |
| 7 |
IMPORTANT:
The 5-volt reference circuits are internally and externally connected to the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnosis the applicable circuits and components. Test the 5-volt reference circuit of the FTP sensor for an open or for a short to ground between the harness connector and the ECM. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems.Did you find and correct the condition? |
- | Go to Step 14 | Go to Step 11 |
| 8 | Test for an intermittent and for a poor connection at the fuel tank in-line harness 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 14 | Go to Step 9 |
| 9 |
|
- | Go to Step 14 | Go to Step 10 |
| 10 | Test for an intermittent and for a poor connection at the FTP 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 14 | Go to Step 12 |
| 11 | Test for an intermittent and for a poor connection at the 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 14 | Go to Step 13 |
| 12 | Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement
. Did you complete the replacement? |
- | Go to Step 14 | - |
| 13 | Replace the ECM. Refer to Engine Control Module (ECM) Replacement
. Did you complete the replacement? |
- | Go to Step 14 | - |
| 14 |
|
- | Go to Step 2 | Go to Step 15 |
| 15 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? |
- | Go to Diagnostic Trouble Code (DTC) List | System OK |