Circuit Description
The fuel injector control module (FICM) monitors the fuel rail pressure (FRP) sensor voltage, and the fuel rail temperature (FRT) sensor voltage. The FICM communicates the data to the PCM by dedicated pulse width modulated (PWM) circuits.
This DTC sets when the rail pressure output PWM signal is not received by the PCM.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | The rail pressure output PWM signal is not received by the PCM. |
| • | The condition exists for at least 5 seconds. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The control module switches over to gasoline fuel operation. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step determines if the condition is present.
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If any of the listed DTCs are set, diagnose those DTCs first.
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This step determines if a FRP sensor circuit may be the cause of the condition. If a FRP sensor circuit condition exists, the FICM will output 0% PWM to the PCM. With the FRP sensor disconnected, the fuel rail pressure should slowly rise.
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This step verifies that the FICM is supplying 5 volts on the FRP sensor reference circuit. An open, or a short to ground, on the 5 volt reference circuit may set this DTC.
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This step verifies that the FICM is supplying a low reference circuit. An open on the FRP sensor low reference circuit may set this DTC.
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This step determines if the signal circuit of the FRP sensor is shorted to a voltage. A short to a voltage on the signal circuit of the FRP sensor may set this DTC.
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This step determines if the signal circuit of the FRP sensor is shorted to ground. A short to ground on the signal circuit of the FRP sensor may set this DTC. The DMM will display OL If the signal circuit is not grounded.
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This step verifies that the FICM is supplying the correct output voltage on the FRP output PWM circuit. The open circuit voltage should be 5.0 volts.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check Alternative Fuels - Engine Controls? | -- | Go to Step 2 | Go to Diagnostic System Check - Alternative Fuels (Engine Controls) |
Observe the FICM odd bank circuit status with a scan tool. Does the scan tool display FAULT? | -- | Go to Step 3 | Go to Step 4 | |
Do any of the DTCs P0187, P0188, P0191, P0192, P0193, or P0611 also set this ignition? | -- | Go to Step 5 | ||
4 |
Does the DTC fail this ignition cycle? | -- | Go to Step 5 | Go to Intermittent Conditions |
Does the scan tool display a pressure at the specified value? | 0 kPa (0 psi) | Go to Step 8 | Go to Step 6 | |
Measure the voltage from the 5 volt reference circuit of the FRP sensor with a DMM. Does the DMM display a voltage near the specified value? | 5.0 V | Go to Step 7 | Go to Step 14 | |
Probe the low reference circuit of the FRP sensor with a test lamp connected to B+. Does the test lamp illuminate? | -- | Go to Step 18 | Go to Step 15 | |
Measure the voltage from the signal circuit of the FRP sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Does the DMM display a voltage less than the specified value? | 1.0 V | Go to Step 9 | Go to Step 17 | |
Measure the resistance of the signal circuit of the FRP sensor, with a DMM, to a known good ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Does the DMM display OL? | -- | Go to Step 10 | Go to Step 16 | |
Does the DMM display the voltage at the specified value? | 5.0 V | Go to Step 19 | Go to Step 11 | |
11 | Is the voltage more than the specified value? | 5.3 V | Go to Step 13 | Go to Step 12 |
12 | Test for an open, or a short to ground on the rail pressure output PWM circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 20 |
13 | Test for a short to voltage on the rail pressure output PWM circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 23 |
14 | Test for an open, or a short to ground on the 5 volt reference circuit of the FRP sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 20 |
15 | Test for an open on the low reference circuit of the FRP sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 20 |
16 | Test for a short to ground on the signal circuit of the FRP sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 23 |
17 | Test for a short to voltage on the signal circuit of the FRP sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 23 |
18 | Inspect for proper terminal contact at the harness connector of the FRP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 21 |
19 | Inspect for proper terminal contact at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 22 |
20 | Inspect for proper terminal contact at the harness connector of the FICM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems in the G/H Van Service Manual. Did you find and correct the condition? | -- | Go to Step 24 | Go to Step 23 |
21 | Replace the FRP sensor. Refer to Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement . Did you complete the replacement? | -- | Go to Step 24 | -- |
22 | Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls in the G/H Van Service Manual. Did you complete the replacement? | -- | Go to Step 24 | -- |
23 | Replace the FICM. Refer to Fuel Injector Control Module Replacement . Did you complete the replacement? | -- | Go to Step 24 | -- |
24 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 25 |
25 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
