fuel pump relay bad again?

[jebadiah04]

My flareside decided to croak again.

Fired it up in the driveway. Turned around. Shut it off and the damn fuel pump won't run again. Luckily I'm getting really good and swapping pumps, I swapped my spare in, nothing. Test benched the pumps...good.

Relay is clicking. What gives?

Relays usually stop clicking when they cook. Think it's the relay? I'm rigging up a bypass wire to see if that fixes it. So I can see if I need another relay. Again.

Which wires should in jump to test?


I should know this by now but I'm special.

 

[jebadiah04]

So I'm stuck good now. Swapped out relays. Still no.prime.

Checked voltage coming into relay I have 2 wires hot key on. 2 not.

Where do I go from here?

No power to pump

 

[fatherdoug]

Not familiar with these years. Is there a fuse for the relay, or an inertia switch?

 

[Fellro]

You can have a relay click and not contact internally. The relay should have a little wiring diagram on top of it to show the connections.

 

[jebadiah04]

Not familiar with these years. Is there a fuse for the relay, or an inertia switch?

No idea.



As far as the relays, I replaced it, still not working.


Is there some kind of fusable link between the relay and the pump?

Anyone know which wire caries the main power?

 

[jebadiah04]

I found the inertia switch, its not tripped, I pushed on it anyways.

 

[jebadiah04]

so I started at the basics, checking every little thing from the relay back.

What I tested for first.

Main Power in. (yellow wire) Was Good

Switch power low current (red wire) -its constant, so it through me off. Was good

The Tan/Green wire is ground from the ECM, so its actually what switches the pump off and on.

Main Power out (brown) - had to wait for it to get dark to be able to see the test light from inside the cab. Cycled on for a half a second or so, then shut off, problem was it would shut down before I got a chance to see the light. But it was good, so I knew at that point, all power in, out, and computer was functioning correctly.


2nd was to trace down what is in between the relay and the fuel pump, I didn't even think about the stupid inertia switch. After checking it, it was in, I dismissed it, however, I decided what the hell and tested in anyways.

Test one, unplug it. No change, fuel pump still didn't prime.

test 2, jump wires with a piece of wire. Fuel pump primed.


So apparently my inertia switch failed internally while driving around in my driveway.

I guess I will need to track down a new inertia switch. But it least its running. Unfortunately it put my back a day on the rest of my projects I need to complete this week due to being broke down in the driveway with my boat attached to it.

its 50 dollars for a new one, I might be living on the wild side for a while until I can track down a cheaper alternative. No way im paying 50 bucks for a switch.

 

[DNFXDLI]

Glad to hear you fingered it out.

 

[jebadiah04]

At least it's something I'm good at.

 

[blackbox90]

Very good trouble shooting skills. What alternative switch you are looking?

 

[jebadiah04]

I just need to get any inertia switch and I'll wire it in. Probably hit the pull and save or pick one up off another member parting one out

 

[Fellro]

If one from an Aerostar would work, I could send that to you.

 

[jebadiah04]

It should, What cha want for it?

 

[Fellro]

Cover the shipping. If you want to do a bit more, that is your choice.

 

[jebadiah04]

Shoot me a pic. I'll see if she will plug in

 

[Fellro]

Well, I guess I am stumped as to where to find it on an 89 Aerostar...

 

[fatherdoug]

'91' and '93' Aerostar was on the passenger's kick panel way back up underneath the dash.

 

[Fellro]

I'll have to get a look...

 

[jebadiah04]

I have no idea why they put them where they do sometimes.

I have heard of the following locations in various vehicles, only ever had to actually track down the one im working on now so none of these are confirmed.

F-150s
Drivers Side Dash, above drivers feet.
Passenger side kick panel
Passenger side about passenger feet behind carpet.

Other cars
Behind paneling in the trunk (ford probe I think?) I believe its was left side, but may have been right side.
behind glove box


Aerostar location from the site we don't talk about

"the inertia switch is located on the side in front of the passenger seat and in front of the door. If you look at the top of the passenger side kick panel under the glove box, you should see the red button for it."

somebody should have standardized location for this switch. Like...fuse box. lol

 

[Fellro]

So, the plug between this inertia switch and the one on the 88 are different. I don't know what one looks like for the prior years, if they are different. The retainer for the plug is on the short side, while the 88 has it on one of the long sides. (Finally 1. remembered, 2. had time to check it out..)