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:

2: Command both the ON and OFF states. Repeat the commands as necessary.
3: This step determines if the condition is located on the coil side or the switch side of the circuit.
7: This step tests for a grounded voltage supply circuit. The fuel pump fuse supplies power to fuel pump. Disconnecting the fuel pump in-line harness connector isolates the fuel pump voltage supply circuit.
9: This step verifies that the fuel pump fuse is providing voltage to the fuel pump relay.
10: This step jumps the fuel pump relay in order to activate the fuel pump.
15: This step determines if the condition with the circuit is intermittent. If the fuse does not open, inspect the supply voltage circuit between the fuse and the fuel pump for an intermittent condition.

Fuel Pump Electrical Circuit Diagnostic

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-Engine Controls?	Go to Step 2	Go to Diagnostic System Check - Engine Controls
2	IMPORTANT: Additional DTCs may set when using the Fuel Pump output control. Turn ON the ignition, with the engine OFF. Command the fuel pump relay ON and OFF with a scan tool. Does the fuel pump turn ON and OFF?	Go to Diagnostic Aids	Go to Step 3
3	Command the fuel pump relay ON and OFF with a scan tool. Do you hear a click when you command the fuel pump relay ON and OFF?	Go to Step 4	Go to Step 16
4	Does the fuel pump operate continuously?	Go to Step 5	Go to Step 6
5	Turn OFF the ignition. Disconnect the fuel pump relay. Turn ON the ignition, with the engine OFF. Does the fuel pump operate continuously?	Go to Step 17	Go to Step 20
6	Is the fuel pump fuse open?	Go to Step 7	Go to Step 9
7	Disconnect the fuel pump harness in-line connector located near the fuel tank. Refer to Power and Grounding Component Views in Wiring Systems. Test the supply voltage circuit of the fuel pump for a grounded circuit. Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Replace the fuel pump fuse if necessary. Did you find and correct the condition?	Go to Step 21	Go to Step 8
8	Lower the fuel tank if necessary. Refer to Fuel Tank Replacement . Test or inspect the fuel tank electrical harness for the following conditions: Damage to the harness A grounded circuit-Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Replace the fuel pump fuse if necessary. Did you find and correct the condition?	Go to Step 21	Go to Step 15
9	Turn OFF the ignition. Disconnect the fuel pump relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the fuel pump relay with a test lamp connected to a good ground. Does the test lamp illuminate?	Go to Step 10	Go to Step 18
10	Connect a 15-amp fused jumper wire between the battery positive voltage circuit and the fuel pump supply circuit of the fuel pump relay. Does the fuel pump operate?	Go to Step 16	Go to Step 11
11	Disconnect the fuel pump harness in-line connector located near the fuel tank. Test the supply voltage circuit of the fuel pump for an open or for high resistance between the fuel pump relay and the in-line connector. Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 21	Go to Step 12
12	IMPORTANT: Inspect the ground circuit for being tight, for corrosion on the terminals, or for damage to the wiring harness. Test the ground circuit of the fuel pump for an open or for high resistance between the body pass through connector and the ground. Refer to Wiring Repairs and Connector Repairs in Wiring SystemsDid you find and correct the condition?	Go to Step 21	Go to Step 13
13	Inspect for poor connections at the fuel pump in-line connector to the body pass through 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 21	Go to Step 14
14	Lower the fuel tank. Refer to Fuel Tank Replacement . Test or inspect the fuel tank electrical harness for the following conditions: Damage to the harness An open circuit-Refer to Wiring Repairs and Connector Repairs in Wiring Systems Did you find and correct the condition?	Go to Step 21	Go to Step 19
15	Connect all disconnected components. Install a new fuel pump fuse. Command the fuel pump ON with a scan tool. Is the fuel pump fuse open?	Go to Step 19	Go to Diagnostic Aids
16	Inspect for poor connections at the fuel pump relay. 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 21	Go to Step 20
17	Repair the supply voltage circuit of the fuel pump for a short to voltage. Refer to Wiring Repairs and Connector Repairs in Wiring Systems. Did you complete the repair?	Go to Step 21	-
18	Repair the battery positive voltage circuit of the fuel pump relay for an open. Refer to Wiring Repairs and Connector Repairs in Wiring Systems Did you complete the repair?	Go to Step 21	-
19	IMPORTANT: Inspect for poor connections at the fuel pump, within the fuel tank, before replacing the fuel pump. Replace the fuel tank module. Refer to Fuel Tank Module Replacement . Replace the fuel pump fuse if necessary. Did you complete the replacement?	Go to Step 21	-
20	Replace the fuel pump relay. Did you complete the replacement?	Go to Step 21	-
21	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2