Hello. i have an 07 GMC sierra 5.3 and it is getting low fuel pressure code po069. if am not really worried about the fuel pressure because the truck runs on propane. what i am worried about is that code affecting the signal that is sent to the injectors to fuel the motor, because that signal is also sent to the LPG ecm to calculate how much propane is injected with propane injectors.

 

Bumpppp

 

This is the closest I can find to that code for that vehicle. Doesn't exactly mean it is low fuel pressure.

DTC P069E: Fuel Pump Control Module Requested MIL Illumination

Circuit/System Description

The fuel pump control module uses the serial data network to signal the engine control module (ECM) that the fuel pump control module is requesting malfunction indicator lamp (MIL) illumination. A DTC is set in the fuel pump control module, and the request for MIL illumination is sent when the fuel pump control module determines that a failure that affects emissions has occurred in the fuel pump control system. When the ECM receives the message from the fuel pump control module, DTC P069E will set in the ECM.

Conditions for Running the DTC

The ignition is ON, or the engine is running for greater than 3 s.

Conditions for Setting the DTC

The fuel pump control module requests the ECM to illuminate the MIL.

Action Taken When the DTC Sets

DTC P069E is a Type A DTC.
DTC P069E will continue to be current or active as long as the fuel pump control module is requesting MIL illumination.

Conditions for Clearing the DTC

DTC P069E is a Type A DTC.

Diagnostic Aids

Communication codes, U-codes, as well as powertrain codes, P-codes, set in the fuel pump control module will cause the fuel pump control module to request DTC P069E to be set in the ECM.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Note:

Do not replace the engine control module for this DTC. DTC P069E is an informational DTC.
Correct any engine controls and communication DTCs before diagnosing fuel pump control module DTCs.

Verify that there are no engine controls or communication DTCs set.

If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for diagnosis of engine control or communications DTCs See: Diagnostic Trouble Code Descriptions.

If a DTC is not set

Verify that there are no fuel pump control module DTCs set.

If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for diagnosis of fuel pump control module DTCs See: Diagnostic Trouble Code Descriptions.

If a DTC is not set

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.
Verify the DTC does not set.

If the DTC sets

Refer to Diagnostic Trouble Code (DTC) List - Vehicle See: Diagnostic Trouble Code Descriptions.

If the DTC does not set

All OK.

 

You are right it was P069E. The code does set I have to manually clear or run the truck on gasoline. Which it does automatically on cold starts. The code usually comes back on longer drives around 30km.

So does this code affect the fueling ?

Should i tune it out ?