need help with fuel pump relay problem

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the ignition key does not intergize fuel pump relay, but i can hook my test light to the positive side of battery and touch the green wire in the relay with test light and the relay kicks on and the vehicle will start. What do i need to do to fix this problem. please help me. thank You so much

[old_master]

Year, make , model, & engine are necessary for help with diagnosis.

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sorry new at this it is a 1992 4.3 eng s10 blazer

[old_master]

What is the 8th character in the VIN, (engine code)? Could be either a "Z" or a "W".

Orange wire at relay should have battery voltage at all times. "ECM B" 10 amp fuse.
Gray wire goes to fuel pump.
Black with white stripe must be less than 5 ohms to ground. (Relay trigger ground)
Dark green with a white stripe comes from ECM; must have battery voltage for 2 to 3 seconds when the ignition is turned to RUN position, and have battery voltage constantly with ignition in the START position. (Relay trigger)

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thanks for the response I am lost the vin is Z the plug is what I have that you discribed . I changed the ign switch (new one) put on used comp. fried one jumping g&w wire ( leaked through alt. ) where should this wire get the volts to energize the relay for 2or3 sec.

[old_master]

Disconnect the fuel pump relay, check each of the wires in the harness connector. You must have the results indicated below:

Orange wire must have battery voltage at all times. (Comes from the "ECM B" 10 amp fuse.)

Gray wire goes to fuel pump. If you apply battery voltage to this wire, the pump must run.

Black with white stripe wire, resistance must be less than 5 ohms to ground. (This is the ground for the relay.)

Dark green with a white stripe wire comes from ECM to trigger the relay. It must have battery voltage for 2 to 3 seconds when the ignition is turned to RUN position, then drop to zero volts. It must have battery voltage continuously with the ignition in the START position. (Relay trigger)

When the relay is energized, it connects the orange wire to the grey wire. Post your results.

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the switch doesn't do it's job is there a plug between comp. and switch to check ? I'm lost the relay unhooked checked out orange wire gray black &GREEN wire was dead unless I jumped it my self

[old_master]

Dark green with white stripe wire runs directly from the ECM terminal A1 to the fuel pump relay, no other connections.

Disconnect the relay, connect your voltmeter positive lead to the dark green/white wire in the relay harness. Connect the voltmeter negative lead to ground. Turn ignition switch to the RUN position and check for battery voltage for 2 to 3 seconds. Then turn ignition switch to the START position and check for constant battery voltage. Post your results.

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I have nothing in run or start with switch I apreciate the help I have been complete lost with newer cars the green &white stripe wire was dead both sides of switch

[old_master]

What "switch" are you referring to?

If the green/white stripe wire doesn't have battery voltage in either ignition position, that is the problem. Check all ECM fuses, (both terminals of each fuse), with the voltmeter. If the fuses are good, check continuity of the green/white stripe wire with an ohmmeter from the ECM harness connector to the relay harness connector. It must be less than 5 ohms.

The ECM 1, (10amp fuse) feeds the pink with black stripe wire that runs to the ECM terminal B4.
Also, there is a pink wire at the ignition coil, it must show battery voltage when the ignition is in the RUN and START positions.

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I still have trob. with this comp. Ijust came in the G&w wire was definitly broke some place . Iwill put it back together as soon as trace it I can't thank you enought
Just knowing where the g&W wire went with no conectors saved me . I am satisfided the problem is here.thanks again&again

[old_master]

Glad I could help. Post the problem/fix when you're done.

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sorry I got excited the g&w wire was not broken nothing coming out of computer with ign switch in start or run position no volts

[old_master]

See post #10.

Also check ECM B 10 amp fuse, it should show battery voltage at all times.

Check pink/black wire at ECM terminal B4. It must show battery voltage when the ignition is in START and RUN positions. This wire comes from ECM 1 (10 amp fuse).

Post your results to all of these tests.

[Schrade]

Originally Posted by old_master

See post #10.

Also check ECM B 10 amp fuse, it should show battery voltage at all times.

Check pink/black wire at ECM terminal B4. It must show battery voltage when the ignition is in START and RUN positions. This wire comes from ECM 1 (10 amp fuse).

Post your results to all of these tests.

I think you might be posting over his head a few times there OM...

Where are you now there, llcope2? What have you been able to check? Do you have a multimeter? Besides a test light?