DTC P0251-P0254
Diagnostic Instructions
DTC Descriptors
| DTC P0251 00: Fuel Pressure Regulator 1
Control Circuit Malfunction |
| DTC P0252 54: Fuel Pressure Regulator 1
Control Circuit High Temperature |
| DTC P0253 00: Fuel Pressure Regulator 1
Control Circuit Low Voltage |
| DTC P0254 00: Fuel Pressure Regulator 1
Control Circuit High Voltage |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Ignition
|
P0253 00
|
P0251 00
|
—
|
P0252 54
|
Control
|
P0253 00
|
P0251 00
|
P0254 00
|
P0252 54
|
|
| |
Circuit/System Description
The fuel pressure regulator is used to control the fuel pressure
at the high pressure pump. The fuel pressure regulator is pulse
width modulated (PWM). The engine control module (ECM) supplies the
voltage directly to the fuel pressure regulator. The ECM controls
the solenoid by grounding the control circuit with a solid state
device called a driver.
Conditions for Running the DTC
| • |
The ignition is ON, or the
engine is running. |
| • |
The ignition voltage is less
than 16 V. |
| • |
The DTCs runs continuously
once the above conditions are met. |
Conditions for Setting the DTC
P0251
The ECM detects the Cam Sensor Control Circuit is open for more
than 1 s.
P0252 54
The ECM detects an overtemperature at the output control driver of
the Cam Sensor.
P0253
The ECM detects that the Cam Sensor control circuit is shorted to
earth for more than 1 s.
P0254
The ECM detects that the Cam Sensor control circuit is shorted to
voltage for more than 1 s.
Action Taken When the DTC Sets
DTC P0251, P0252 54, P0253 and P0254 are type A DTCs.
Conditions for Clearing the DTC
DTC P0251, P0252 54, P0253 and P0254 are type A DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
| 1. |
Ignition ON, observe the DTC
information with a scan tool. DTCs P0251, P0252 54, P0253 or P0254
should not set. |
| 2. |
Operate the vehicle within the
Conditions for Running the DTC to verify the DTC does not reset.
You may also operate the vehicle within the conditions that you
observed from the Freeze Frame/Failure Records data. |
Circuit/System Testing
| 1. |
Ignition OFF, disconnect the
harness connector at the Q18 Fuel Pressure Regulator. |
| 2. |
Ignition ON, verify a test
lamp illuminates between the ignition voltage circuit terminal 1
and ground. |
| ⇒ |
If the test lamp does not illuminate, test the
ignition voltage circuit for a short to ground or an open/high
resistance. If circuit tests normal, replace the K20 Engine Control
Module. |
| 3. |
Ignition ON, test the voltage
between the control circuit terminal 2 and ground. The voltage
should be within 3–4 V. |
| ⇒ |
If less than the specified range, test the control
circuit for an open or a short to ground. If circuit tests normal,
replace the K20 Engine Control Module. |
| ⇒ |
If greater than the specified range, test the
control circuit for a short to voltage. If circuit tests normal,
replace the K20 Engine Control Module. |
| 4. |
Test for less than 5 Ω
on the ignition voltage circuit and the control circuit.
|
| ⇒ |
If greater than the specified range, repair the
appropriate circuit for a high resistance. |
| 5. |
If all circuits test normal,
test or replace the Q18 Fuel Pressure Regulator. |
Component Testing
Static Test
| 1. |
Ignition OFF, disconnect the
harness connector at the Q18 Fuel Pressure Regulator. |
| 2. |
Test for 2.5–3.5 Ω
between the control terminal 1 and the ignition voltage terminal
2. |
| ⇒ |
If not within the specified range, replace the Q18
Fuel Pressure Regulator. |
| 3. |
Test for infinite resistance
between each terminal and the solenoid Q18 Fuel Pressure
Regulator. |
| ⇒ |
If not the specified value, replace the Q18 Fuel
Pressure Regulator. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
