Newton Posted May 25, 2016 Share Posted May 25, 2016 OK so my pump went bad and this happened all of a sudden..well assuming it did took it out hooked it up directly to battery no buzzing or any life whatsoever so i bought a new fuel pump put it in now truck doesnt want to start i don't hear the pump priming when i turn on ignition pump works when i hook it up directly checked that orange live wire traced it all the way to the fuel pump relay and its not broken swapped the relays around still nothing ballast has continuity but i read somwhere that i was suppose to get 12 volts on pin 30 at the relay but I'm getting 0 ..checked the relay next to it and there 12 volts on pin 30 but not on the fuel pump relay socket can someone please tell me what i should check next? Link to comment Share on other sites More sharing options...
88whitemanche Posted May 25, 2016 Share Posted May 25, 2016 Did you check the fuel pump ballast? Right by the air box? Link to comment Share on other sites More sharing options...
ftpiercecracker1 Posted May 25, 2016 Share Posted May 25, 2016 88whiteComanche, he already checked that. Go as far Upstream in the circuitry as you can, apply 12 volts and see if the pump works. If it works you know your problem lies farther Upstream, if it doesn't you know your problem is somewhere between that point and the pump. Link to comment Share on other sites More sharing options...
Marine1Texas Posted May 25, 2016 Share Posted May 25, 2016 hows your ground to the fuel pump? did you do the refresh grounding behind the rear driver tail lamp? Link to comment Share on other sites More sharing options...
Newton Posted May 25, 2016 Author Share Posted May 25, 2016 yes ballast is good tried bypassing it as well still no power..ground behind tail lamp is good ive checked up to fuel pump relay don't know if there is something else I'm missing and what more weird about it is a couple days ago the truck worked fine didnt start it for about 2 days when i tried to start it after that ..nothing...bought the delphi fuel pump from autozone which doesnt even fit in my tank which i think is an 18 gallon cut off the line up tabs on it so it could sit in tank don't even know if its gonna work but atleast id like to get some power to it so i can try it..damn blasted thing :fs1: hows your ground to the fuel pump? did you do the refresh grounding behind the rear driver tail lamp? 88whiteComanche, he already checked that.Go as far Upstream in the circuitry as you can, apply 12 volts and see if the pump works. If it works you know your problem lies farther Upstream, if it doesn't you know your problem is somewhere between that point and the pump. Did you check the fuel pump ballast? Right by the air box? Link to comment Share on other sites More sharing options...
Newton Posted May 25, 2016 Author Share Posted May 25, 2016 no power is coming to the fuel pump relay socket why is that? Link to comment Share on other sites More sharing options...
Marine1Texas Posted May 25, 2016 Share Posted May 25, 2016 did you check fusible link at the starter relay? When you check the relay harness plug in, did you get all the time power to the #79? Link to comment Share on other sites More sharing options...
Newton Posted May 25, 2016 Author Share Posted May 25, 2016 did you check fusible link at the starter relay? When you check the relay harness plug in, did you get all the time power to the #79? how do i check the fusible link at the starter and also the #79...please excuse me i'm a lil new to this Link to comment Share on other sites More sharing options...
Newton Posted May 25, 2016 Author Share Posted May 25, 2016 neither the b+ latch relay nor the fuel pump relay has voltage at pin 30 all the rest do Link to comment Share on other sites More sharing options...
Marine1Texas Posted May 26, 2016 Share Posted May 26, 2016 Sorry auto corrected on my phone 87 not 79. 1st did you try jumping pin 87 with 12 volt to see if it would turn the pump on? If that turns pump on then you can check pin 30 and 86. 2nd Since you said 30 has not power check the fusable link. it is like a inline fuse that is wrapped. That may be blown or have a bad wire connection. You may have to replace it if it is bad. I think it is 20 or 25A don't hold me to that number not at my computer right now. 3rd the 86 which is wired to the starter relay. easy enough to test if it is getting power by Turing ignition to on, and checking if you have voltage there. If you can not get power to 30 you can always run a hot 12volt from battery connector with a fuse between battery and Pin 30. It is only pulling juice when your ignition is turned on. Link to comment Share on other sites More sharing options...
Newton Posted May 26, 2016 Author Share Posted May 26, 2016 ok so i have a ground coming to pin 30 85 and 87 on the fuel pump relay i'm guessing this shouldnt be? Link to comment Share on other sites More sharing options...
cruiser54 Posted May 26, 2016 Share Posted May 26, 2016 ok so i have a ground coming to pin 30 85 and 87 on the fuel pump relay i'm guessing this shouldnt be? Should not be. Open up the harness below the fuel pump relay socket. Link to comment Share on other sites More sharing options...
Newton Posted May 26, 2016 Author Share Posted May 26, 2016 ok so i have a ground coming to pin 30 85 and 87 on the fuel pump relay i'm guessing this shouldnt be? Should not be. Open up the harness below the fuel pump relay socket. i opened up the harness below the relay an orange wire is strip but its not touching anything is it possible something could be grounding under dash also getting ground going to the trans fuse under dash? Link to comment Share on other sites More sharing options...
cruiser54 Posted May 26, 2016 Share Posted May 26, 2016 ok so i have a ground coming to pin 30 85 and 87 on the fuel pump relay i'm guessing this shouldnt be? Should not be. Open up the harness below the fuel pump relay socket. i opened up the harness below the relay an orange wire is strip but its not touching anything is it possible something could be grounding under dash? 30 should be power from the battery via the latch relay 86 is ignition power with key On 85 is the relay's ground to the ECU 87 is power to the fuel pump Power goes through the C103 connector by the RH shock top. Flat 6 wire connector. Then through cC00 on the firewall side of the fusebox Then C119 behind the driver's side kick panel. 10 wire connector. Link to comment Share on other sites More sharing options...
Eagle Posted May 26, 2016 Share Posted May 26, 2016 ok so i have a ground coming to pin 30 85 and 87 on the fuel pump relay i'm guessing this shouldnt be? Should not be. Open up the harness below the fuel pump relay socket. i opened up the harness below the relay an orange wire is strip but its not touching anything is it possible something could be grounding under dash also getting ground going to the trans fuse under dash? You don't "get a ground" to anything. Ground is ground. Fuses go in power (hot) leads, not ground leads. If you "get a ground" to a fused lead, you have a short circuit that instantly blows any fuse you put in the fuse holder. Link to comment Share on other sites More sharing options...
Newton Posted May 27, 2016 Author Share Posted May 27, 2016 Found out it was the new delphi fuel pump I put in the tank was causing a short circuit somehow was not sitting properly in there..and damn that pump is loud can't hear myself think in the cab is it suppose to be buzzing this loud? Link to comment Share on other sites More sharing options...
cruiser54 Posted May 27, 2016 Share Posted May 27, 2016 Wow. So, when you were checking for power at the pump connector it was still plugged in? And no, should not be loud. Link to comment Share on other sites More sharing options...
Appstate97 Posted June 19, 2017 Share Posted June 19, 2017 I've searched and read a bit on the topic of the fuel rail not priming and I have a few questions. On friday my truck shut off. When trying to restart I noticed that I didn't hear the pump priming. I got the truck towed home and started researching. In Feb. 2017 I refreshed the grounds. Could the grounds need to be refreshed again? I was thinking about refreshing the dip stick ground due to oil build up. I've checked the volts on the fuel pump relay when the key was on and got 12v when grounded to batt and touched to 86. Ground to 30 got me 4.6v. Then I checked the orange (power?), gray (no clue), and black (ground) wires by the fuel tank I got 6.97v with the key on. I am trying to pin point the failure before spending a ton of money. Any help would be great. Link to comment Share on other sites More sharing options...
Appstate97 Posted June 19, 2017 Share Posted June 19, 2017 When I went batt power to 87, the fuel pump turned on and I got fuel to the fuel rail. I need to rent/borrow a fuel pressure gauge for the auto parts store to find out how much pressure I a, getting to the rail. Link to comment Share on other sites More sharing options...
cruiser54 Posted June 19, 2017 Share Posted June 19, 2017 You should have about 12 volts to the pump, not 6.97. Pull the relays and clean up their contacts and receptacles. Link to comment Share on other sites More sharing options...
Appstate97 Posted June 19, 2017 Share Posted June 19, 2017 You should have about 12 volts to the pump, not 6.97. Pull the relays and clean up their contacts and receptacles. Thanks. I'll use electronics cleaner and update later tonight. Do you think I should buy a fuel pressure gauge or clean everything first? Link to comment Share on other sites More sharing options...
Ωhm Posted June 19, 2017 Share Posted June 19, 2017 ................ Ground to 30 got me 4.6v................ I'll assume relay is removed. C216_1 should have B+ voltage. Check voltage at C106_D1-5, should have B+ voltage. Check voltage at C103_B (Engine harness side), should have B+ voltage. Pls advise. Link to comment Share on other sites More sharing options...
cruiser54 Posted June 19, 2017 Share Posted June 19, 2017 ................ Ground to 30 got me 4.6v................ I'll assume relay is removed. C216_1 should have B+ voltage. Check voltage at C106_D1-5, should have B+ voltage. Check voltage at C103_B (Engine harness side), should have B+ voltage. Pls advise. Thank you... Link to comment Share on other sites More sharing options...
Appstate97 Posted June 19, 2017 Share Posted June 19, 2017 ................ Ground to 30 got me 4.6v................ I'll assume relay is removed. C216_1 should have B+ voltage. Check voltage at C106_D1-5, should have B+ voltage. Check voltage at C103_B (Engine harness side), should have B+ voltage. Pls advise. I'm looking at a relay diagram and can't figure out what the A is the C106 comes out of. Also, I took the relay bracket off and placed the red on the batt + and the ground on C216 from the bottom of the fuel pump relay. It read just under 12 with key on. Link to comment Share on other sites More sharing options...
Ωhm Posted June 20, 2017 Share Posted June 20, 2017 Pull the relay out. Take measurements from the pin to any ground. Refer to the following link: http://www.bteventures.com//mj1988electricalmanual.pdf Engine schematic: pg 14 Harness view: pg 89 & 90 Connector view: pg 75 C106_D1-5 is the connector with the yellow cover on it. Link to comment Share on other sites More sharing options...
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