Mechanics

FUEL RELATED

2002 GMC Sierra

Electrical problem
2002 GMC Sierra V8 Four Wheel Drive Automatic 100594 miles

Truck was parked two nights ago with low fuel. Next time I tried to start it, it would not. I assumed the 10 month old fuel sending unit went bad and warrantied the sending unit(oem part). Made no difference. I have noticed the fuel gauge doesn't work(currently has about a half tank of fuel) and the highlight on shift indicator that tells what gear it's in is no longer there. &Quot; Fuel" fuse shows power on both sides with key on, " Fuel" relay shows no power at all where it would plug in to fuse box. I jumped from DRL relay to fuel only to get truck home and it did start. However, once I put truck in reverse to move it, truck died and i'm back with the same problem. Any advice?Thank you for your time.
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Gregnexa
August 26, 2010.



Terminal 30 at the fuel pump relay, shows to be hot all the time.


http://www.2carpros.com/forum/automotive_pictures/170934_gmc_sierra_fuel_pump_relay_1.jpg


JDL
Aug 27, 2010.
No, terminal 30 does not show hot with key on, previously I jumped from drl relay(#30) to fuel(#30) and truck started until I moved from park position

Tiny
Gregnexa
Aug 27, 2010.
It gets voltage from the ecm B fuse.

JDL
Aug 28, 2010.
Where is the ecm b fuse located? Is it in fuse box under hood?

Tiny
Gregnexa
Aug 28, 2010.
Yes, underhood fuse block. Your owners manual should give fuse location and label, if not, maybe I can find a picture?

JDL
Aug 28, 2010.
If u could find a picture that would be great, seeing as my truck did not come with a owners manual. I appreciate all your help!

Tiny
Gregnexa
Aug 28, 2010.
Do you have any idea on what would've caused this to occur?

Tiny
Gregnexa
Aug 28, 2010.
I'd have to check for voltage at the ecm B fuse. Maybe a wiring circuit problem? If the fuse is blown, a faulty fuel pump might cause it. In the picture, fuse number 30-- 20 amp should be the ecm B fuse. You should be able to look at an online owners manual for free. gmownerscenter.yahoo.com, try that link.


http://www.2carpros.com/forum/automotive_pictures/170934_sierra_underhood_fuse_box_1.jpg


JDL
Aug 28, 2010.
Dude, I dont know who you are or what state you live in, but you are the man! Truck is back up and running. Thank you so much for your help and if you're ever in tulsa please let me know, I owe ya a cold beer and a steak dinner. Thanks again!

Tiny
Gregnexa
Aug 29, 2010.
Glad you got it going your way.

JDL
Aug 30, 2010.