Fuel pump relay location and wiring diagrams please?

Tiny
99S10EXTREME
  • MEMBER
  • 1999 CHEVROLET S-10
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 131,327 MILES
Please I need an answer.I unplugged the fuel pump turned the key to reset the pump plugged it back in.I checked the fuses they are good even checked the relay to the pump. Still not coming on or making any sound it worked good the day before. I even checked the grounds at the back of the truck. Everything has power except the fuel pump.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:40 AM (Merged)
Tiny
INTERNETMECHANIC
  • MEMBER
Did you use a voltage tester on the circuits in question? At the fuel pump connector, gray is voltage, check with engine cranking. Black wire is ground. If no voltage, start by checking voltage circuits at the relay.

Also, disconnect voltage to injectors, when testing the pump. The fuel pump relay, also supplies voltage to the injectors.


https://www.2carpros.com/forum/automotive_pictures/512072_chevy_s10_fuel_pump_1.jpg

Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:40 AM (Merged)
Tiny
MICHAELDLEWIS
  • MEMBER
  • 1998 CHEVROLET S-10
  • 4 CYL
  • 2WD
  • MANUAL
  • 225,000 MILES
Im not getting a voltage at ANY of the fuel pump relay female connectors with my working volt meter. Fuel pump doesnt come on so im trying to test pcm and etc but shouldnt I get a voltage at the 'constant' even if pcm bad?
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:40 AM (Merged)
Tiny
HMAC300
  • EXPERT
Yup is fuse good? If not it may be a fuse box problem. It's ecm b fuse check with voltmeter to see if power goesthrough it then if not getting to relay problem I sthere. Gray wire goes to pump drk grn from pcm of course black is ground.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:40 AM (Merged)
Tiny
DUCKSHARP
  • MEMBER
  • 1996 CHEVROLET S-10
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 188,000 MILES
I have recently took on a project of restoring a 1996 chevy s10 ZR2 pickup truck. I have just recently replaced the raidator supoort to a 1998 model, I had to replace the front cap and like the newer model front end. I dont know the history of the truck I tolled it home. I not very mechanically inclined that is to say I know very little about vehicles. Now to my question, I having problem with the fuel pump "I think" I have check the ECM battery fuse it test good Im getting 12 volts at the fuse box. I have check the fuel pump relay by switching it with the horm relay it check out good i'm also getting 12 volts thier to. I have unpluged the fuel pump module from the gas tank not sure what that does the book I have says it for fuel level sending unit and full pump 12 volt supply. Is that what send the imformation to the gas gauge needle on the cluster? And is that all it does? It also has a 3 wire plug on the fuel pump module "not sure what that does" I think it the power supply for the pump. Is this correct? I have check the power supply to both of these plugs and i"m only getting 6 volts unless I jumper a wire from the battery to the fuel pump test terminal then i'm getting 12 volts. I would like to know what prongs on the 2 plugs should be sending volt reading. That about all I know I would really like to exhast all other option before repalceing the fuel pump. I here so many comments about people replacing there full pump just to find out that was not it.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
RASMATAZ
  • EXPERT
Hi ducksharp, Welcome to 2carpros

Power the fuel pump gray wire at the fuel pump connector from the battery positive post and tell me if it comes on-let me know
Was this
answer
helpful?
Yes
No
-1
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
DUCKSHARP
  • MEMBER
I ran the wire from the positive post to the gray wire conector i'm getting 12 volts to the plug, but the fuel pump did not come on. I tried with key in the on postion and off. Does the fuel pump module or the 4 prong switch need to be plug in when performing this test?
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
RASMATAZ
  • EXPERT
The connector has to be plugged -in

Check the ground circuit black wire at inside left frame rail, if its okay-the fuel pump is defective-also check the other grounf for the sending unit at rear of right cyl head-See below


https://www.2carpros.com/forum/automotive_pictures/12900_fp_62.jpg

Was this
answer
helpful?
Yes
No
+2
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
DUCKSHARP
  • MEMBER
I have put a new fuel pump on my truck, but still is not coming on. I not getting nothing through the gray wire 6 volts through the purple wire when key is on. I have check the the wire with a meter on the black and gray wire and I am getting nothing should it show some kind of reading? Do I need 12 volts through the gray and 12 volts through the purple? I really not sure how the wiring harness color code works. The harness wire color are black/white, purple, gray and solid black the same as my orginal wire on my truck I mayched by color is that right? Is thier anything I may have un plug when I replace my radiator support? I unplug the wiring harness for the lights on the passanger side when I replaced. I still get 12 volts in the fuse box and 12 volts through the relay.
Was this
answer
helpful?
Yes
No
-1
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
DUCKSHARP
  • MEMBER
Im sorry I unplug the driver side light harness when I replaced my radator support.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
DUCKSHARP
  • MEMBER
I have ran a wire from the battery hot post and used the black ground wire from the truck to the fuel pump module and the pump comes on, but I cannot get any power to the gray wire at the fuel pump module. Any suggestion? Where does the gray wire go after it leaves the fuel pump module? I have 12 volts at the fuse box and relay. Can it be the oil pressure switch?
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
RASMATAZ
  • EXPERT
Depending on the 8th digit of the VIN number (Yours is a transition year) it may have a oil pressure switch for the fuel pump. If so I have seen many go bad. See the wiring diagram below
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
RAZEY
  • MEMBER
  • 1996 CHEVROLET S-10
Put on a new fuel pump and have no power to the pump. Is there a relay and if so where
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
RASMATAZ
  • EXPERT
Fuel Pump Relay Fog Lamp I/P Wiring


https://www.2carpros.com/forum/automotive_pictures/12900_fpr_18.jpg


Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:41 AM (Merged)
Tiny
CECIL ANDREWS
  • MEMBER
  • 1996 CHEVROLET S-10
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 160,000 MILES
1996 S10 Blazer (4.3 4WD). Turned over but wouldn't start. It started with starting fluid so I replaced the fuel pump. New pump didn't help. Checked plug to the pump and had about 6VDC for about 2 sec. Plug did not appear to have a ground connection. Tapped solid black wire with a ground connection but didn't help. Tried to test wires but am getting conflicting info on location of Fuel Pump relay. Voltage checks do not seem to match my diagrams so I'm not sure if I am on the correct relay plug. Can you give me some guidance?
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:42 AM (Merged)
Tiny
RASMATAZ
  • EXPERT
Behind glove box, on relay center. See below location no.3
Was this
answer
helpful?
Yes
No
-1
Saturday, March 6th, 2021 AT 11:42 AM (Merged)
Tiny
HENRY HOOKER
  • MEMBER
  • 1996 CHEVROLET S-10
  • 4.3L
  • V6
  • 2WD
  • AUTOMATIC
  • 170,000 MILES
Okay, I have the truck listed above being converted to a 5.3 LS. I need to know the location and color of the factory fuel pump power wire to connect a 5.3 harness fuel pump wire to. There's pull relays mounted to the back of the firewall I don't know which one is which or what wire do what. Please help me.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:42 AM (Merged)
Tiny
DL AUTOSHOP
  • MEMBER
Hello, I'm Danny.

Here is a fuel pump wiring diagram for your truck. Hope this helps and let me know if you need any further wiring diagrams to make your LS swap work. Picture is attached below. Hope this helps and thanks for using 2CarPros.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:42 AM (Merged)
Tiny
TAMEY_K
  • MEMBER
  • 1995 CHEVROLET S-10
Plz tell me where to find the fuel pump relay on my 1995 s10 2wd 4 cyl. Also I would love to have a
osu diagram I replaced the fuel pump (had some one do it)about 3 to 4 years ago. Now im having problems while driving, even after it sits all night it will occassionally just shut down, sometimes re starts or not start at all. Later it will.
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:42 AM (Merged)
Tiny
RASMATAZ
  • EXPERT
Okay the fuel pump relay is at no.3 and the OSU is on no.8 above the A the square box and your fuel pump/oil sending unit electrical circuit is below that.


https://www.2carpros.com/forum/automotive_pictures/12900_1995_S10_fuel_pump_realy_and_oSU_1.jpg




https://www.2carpros.com/forum/automotive_pictures/12900_oil_sending_unit_and_fuel_pump_circuit_10.gif



Good LUck and have a nice day
www. .com
Was this
answer
helpful?
Yes
No
Saturday, March 6th, 2021 AT 11:42 AM (Merged)

Please login or register to post a reply.

Sponsored links