Test Description

WARNING: This page is about a different car, the 2006 Buick LaCrosse and 2006 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.

The number below refers to the step number on the diagnostic table.

4: This step verifies that the control module is providing voltage to the fuel pump relay.
5: This step tests the ground circuit of the fuel pump relay.

DTC P0627 Fuel Pump Relay Control Circuit Open

Step	Action	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 - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2	IMPORTANT: DTC P2105 may cause this DTC to set. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information. Additional DTCs may set when using the Fuel Pump output control. Turn ON the ignition, with the engine OFF. Command the fuel pump ON and OFF with a scan tool. Does the fuel pump relay turn ON and OFF with each command?	Go to Step 3	Go to Step 4
3	Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 4	Go to Diagnostic Aids
4	Turn OFF the ignition. Disconnect the fuel pump relay. Turn ON the ignition, with the engine OFF. Probe the control circuit of the fuel pump relay with a test lamp connected to a good ground. Command the fuel pump ON and OFF with a scan tool. Does the test lamp turn ON and OFF when commanded?	Go to Step 5	Go to Step 6
5	Connect a test lamp between the control circuit and the ground circuit of the fuel pump relay. Command the fuel pump ON and OFF with a scan tool. Does the test lamp turn ON and OFF when commanded?	Go to Step 7	Go to Step 9
6	Test the control circuit of the fuel pump relay for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 12	Go to Step 8
7	Test for an intermittent and for a poor connection at the fuel pump relay. Refer to Testing for Intermittent Conditions and Poor Connections andConnector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 12	Go to Step 10
8	Test for an intermittent and for a poor connection at the engine control module (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 12	Go to Step 11
9	Repair the open or high resistance in the ground circuit of the fuel pump relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 12	-
10	Replace the fuel pump relay. Did you complete the replacement?	Go to Step 12	-
11	Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup and programming. Did you complete the replacement?	Go to Step 12	-
12	Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 2	Go to Step 13
13	Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?	Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information	System OK