1995 Bonnevile Gray Wire to Pump No Voltage

[sixsmiles]

My 95 Bonneville has no power to gray wire on Fuel pump. I replaced the relay, with no luck. When I run a jumper (Paper clip) between 30 and 87 on the fuse box it has power. Shop manual says CHK 50 could be open if the jumper works, but I am lost on how to fix check wire?

[maxwedge]

Originally Posted by sixsmiles

My 95 Bonneville has no power to gray wire on Fuel pump. I replaced the relay, with no luck. When I run a jumper (Paper clip) between 30 and 87 on the fuse box it has power. Shop manual says CHK 50 could be open if the jumper works, but I am lost on how to fix check wire?

Check wiring diagrams for this circuit on autozone.com/repairinfo, then enter your car info and go to repair guides, look at chassis schematics.

[richtazz]

did you check the fuel pump fuse?

[sixsmiles]

I have checked the 15 Amp fuse and it was fine. Checking Autozone diagram Shop manual is not a lot of help.

[sixsmiles]

Is the fuel pump check wire the wire next to the battery? It has a female blade connector, and is green?

[Mickey#1]

Yes. it's the wire by the battery. You didn't say how you checked it. When the key is turned to the run position the PCM energizes the relay for just 2 seconds. This is to prime the fuel rail. So if you turn the key to run then get out and check for power you'll be too late. You should have constant power while key is in start position & of course after it starts. Engine not starting?

[sixsmiles]

Thanks Mickey #1, yes I checked it with my son turning on the key, and I was at the gray wire on the pump. Checked it several times, and also confirmed that the voltage was present to the gage sending unit... just to make absoultely certain the volt meter was working correctly.
Thanks for the location of the pump test circuit... near the battery.

[Mickey#1]

I'm looking at a wiring diagram for a 95 VIN K. Relay terminal 85 gets +12 volts from PCM & grounds through terminal 86 to energize the relay. Check for power between those terminals. Did you check all the fuses?

Let me know is the engine is a VIN K (8th digit in VIN). PM me with an email address if you want a copy of the wiring diagram.

[sixsmiles]

Thank you so much! It is a K engine code I did check all fuses, but will get the voltage tonight, and recheck fuses

[Mickey#1]

I'd better give you as much info as possible so you can solve this quickly.
Here's the portion of the wiring diagram that covers the fuel pump.



It looks like the wire by the battery shouldn't be called a test lead for your year. Let's call it the prime connector. If you were to run a jumper from the Pos. battery terminal to the prime connector the relay would route power (with key in off position) from 87a to 30. Note that the fuel pump has a secondary power supply from the oil pressure switch.

When you check for power between 85 & 86 make sure to look for both the two second prime (key in run position) and constant power while the key is in the start position.

If you're not getting power between 85 & 86 you need to check for spark. I'll check back later to see what you found.

[sixsmiles]

Thank you all so much for the help!!! I finally checked terminal 86 and it was hot... black and white wire, I grounded this wire, and the fuel pump works perfect ... wish I would have done this before I changed the fuel pump twice!!!