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98 OBW fuel pump relay location


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Could my fuel pump (FP) relay be colored black in an 98 OBW? I checked my voltages at the FP and none of them run up to the 12.5v my battery has. I checked the connect under the passenger seat. I have seen multiple post that mention the green relay but the fuse panel but there are three relays on mine and all of them are black. The factory security alarm box is stuff and zip tied right in front of these so just pulling them will be hard.

 

Put on used pump and I still don't get fuel pumping out at the under the hood filter.

 

What location on the 6 pin connector should I get a full 12v reading?

 

thanks,

 

Michael

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The way I find it is with a mechanics stethoscope. It will click on for about two seconds each time the key goes from acc to run. Then with the mechanics stethoscope you can pinpoint exactly which relay it is.

 

Now of course the relay has to be functioning properly to hear it click. But that brings about a couple other thoughts. When are you measuring the voltage at the fuel pump? It doesn't run the fuel pump unless the engine is running, or as noted for a couple seconds when the key goes acc to run. Else you will not see voltage there because it isn't supposed to be running.

 

Other thing that has been seen a few times is the transistor in the ECU that drives the fuel pump relay going flaky/bad.

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Thanks for the reply porcupine. I have checked the voltage at the FP connection with my wife turning the key. I get erratic voltage w my digital reader. The reading jumps around for a second or two but nothing near 12 v. I see 4v to around 8.5 at it highest.

 

Some suggest taking off the fuse panel. I took off the knee panel and tried to take off the fuse panel (with the fuses in it). All I could find was a 10mm nut on the bottom and some side clips but it won't budge. But it doesn't look like removing the fuse panel will gain much.

 

Should I take off the top of the dash?

 

I need an instrument cluster bulb replaced to please my wife so I don't mind digging into it. But I really just want to get to the FP relay.

 

thanks,

 

Michael

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I thought the Fuel Pump gets power with the key in the on position when the car is first turned on.

 

With taking apart more of my dash I got a peak at one of the relays 10in above the fuse panel. I still don't see a way to get up in there to replace it with taking the alarm box and multiple wire clips out of my way. I am real bad with those clips and can't get some of them apart.

 

Attached is a pic from ankle level looking up.

 

How do I take out the fuse panel?

 

Should I take out the alarm box and work my way up to the relay?

 

thanks

 

Mike

post-14789-136027653056_thumb.jpg

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Update...I connected the green clips to get the relays cycling. At the FP connection, I get a jumping signal that goes up to 8 to 9 volts then off. I suspect the replacement pump I got is bad and I give up trying to get to relay. I will wait the week to get a second replacement and try that route. thanks guys

 

Mike

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Sounds like you have voltage at the pump and the relay is working. The ECU cycles the pump for about 1.5 seconds when you firs turn the key on then will only run the pump continuously if you are cranking or the engine is running (tach signal present).

 

If you suspect the pump is bad then run 12v directly to it and see if it comes on. Should be really simple to test. I have a jump pack for starting dead cars and I use that for things like fuel pump testing. Couple aligator clipped test leads and you'll know for sure.

 

GD

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With a online search I see the FSM is the factory service manual. It that available in this site?

 

I should have been more thorough with my testing before I went for the relay.

 

Is there a listing of the fuse panel on this site? I lost my cover for the fuse panel.

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FSM is available somewhere via this site, I don't recall where anymore.

 

According to my '99 FSM fuse 4 in the fuse block under the dash is for the fuel pump (I think its a 15 amp). The fuel pump relay is powered from fuse 3 in the engine compartment fuse box.

Edited by Mike104
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Second replacement pump work. Tested it before I put it in. But now my front yellow lights and rear driving lights won't turn off. Cycled thru the security alarm after reconnecting battery and they still won't turn off. I have unplugged the green relay connection and thought I put my dash back together. Any ideas? thanks for the help so far and in the future.

 

Michael

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