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Topic: Fuel Pump Relay - Help! (Read 4393 times) previous topic - next topic

Fuel Pump Relay - Help!

Reply #15 –
This is why I recommended to keep the overlay "in circuit" and before the inertia switch.  He's right, if you take power from another circuit, you may back feed the circuit.  This circuit includes such components as the injectors, so it would be good to test for power from the eec relay out until you find a ball of snot or a cut circuit.  I still suspect the circuit between S532 and the inertia switch, because if the eec relay were bad, the engine would not run.  The eec would not power up, the injectors would have no power, etc.  As long as you can jump Y to R WITH THE INERTIA SWITCH OUT, and have the engine run, I'd say your eec relay is validated.  You're almost certainly looking for a wiring problem.

Fuel Pump Relay - Help!

Reply #16 –
My "temp" red key-on overlay goes to the trunk and is spliced in at the fuel pump relay connector.  The original red is cut, so I don't think I would get a backfeed. Jcassity, I agree, if I had just tied in a new red, power could backflow through the circuit.  Now if you flip over to the 5.0 page of this circuit, there is the additional connector 491 which joins the pink/blk-s from the inertia switch to the red 361 circuit.  The car runs fine, everything else works, so I think I have it narrowed down to either the inertia switch itself, or the wiring loop from C491 to it.  I know I stated earlier that I jumpered the inertia switch with no luck, but I can't remember if I had the relay plugged in or not, so that is someting I have to verify, after returning the wiring to stock.  As it is now though, the inertia switch is bypassed.
One interesting thing though, my temp.,in-line fused, red key-on is connected at the fuse block at a point that is also "accessory-on".  So turning the key to accessory makes the fuel pump run.  Apparently the ECA creates that ground at pin 22 when it is powered down which trips the fuel pump relay if it is getting power at the red.  So I tried for a hot-in-run point at the fuse block but my initial attempt failed.  That red needs hot-in-run+start to keep the pump running as the engine cranks.  I did't have a chance to mess with it today, but I'm climbing in that trunk tomorrow in search of elusive C491!

Fuel Pump Relay - Help!

Reply #17 –
Does the SES light come on when keyed??? If yes the EEC relay is working.  If no the EEC relay is KAPUT!!! If the back feed you performed is after the inertia switch and the inertia is tripped or removed you are not back feeding.

Check voltage at 37/57 of the ECM for battery when ignition is keyed. IS IT THEIR  YES EEC IS OK. Or is the SES light on when keyed  YES EEC IS OK!!! Install noid light in one injector connector crank does noid light blink?? Yes EEC OK. NO EEC KAPUT!!!

Best way to check the EEC relay is to see if the SES Light comes on with the ignition keyed. It supplies battery to pins 37/57 and powers up the ECM.
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel Pump Relay - Help!

Reply #18 –
"Check Engine" light comes on with key on.  EEC relay can be heard clicking on under pass side of dash.  Engine starts literally on first crank, runs fine, "Check Engine" light goes out.  My plan is to reconnect stock red at fuel pump relay, remove temp red. Check for power on both sides of inertia switch.  If it goes in and doesn't come out, this would indicate to me a bad inertia switch.  If it goes in and comes out, then I will check at C491. If it comes out of 491 then the break is in the wire from 491 to the fuel pump relay connector which is literally across the top of the trunk from one side to the other.  If juice is not going into 491, then its broke between there and S532 going forward, which I guess is worst case scenario.  JHC, its taking longer to type out than to probably actually test, but tomorrow should tell the tale.

Fuel Pump Relay - Help!

Reply #19 –
I haven't looked at mine in all this, but I seem to remember that C491 is the pigtail on the Inertia switch. C491 is where you're going to have your inertia switch disconnected from.  On 5.0L cars, between C491 and S532 is C455, which according to the location chart is under the IP on the right side, probably near the PCM.  Don't forget C455 in your check list.

Fuel Pump Relay - Help!

Reply #20 –
Wire the dam thing to a KEY battery in series with a fuse and call it a DAY!!!!!!!!!!!!!!!

No sense in ripping the wiring harness open for this situation!!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel Pump Relay - Help!

Reply #21 –
page 223 shows the location of c491.

Fuel Pump Relay - Help!

Reply #22 –
Not a mystery.

HERE YOU GO> Connector C491: RH Front Of Luggage Compartment
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Fuel Pump Relay - Help!

Reply #23 –
Quote from: hwy73;391963
  The original red is cut, so I don't think I would get a backfeed!

 
well you should have siad that instead of "dont ask me how".

essentially you did end up performing the verification step and it proof tests as pass.

Fuel Pump Relay - Help!

Reply #24 –
Jcassity what I meant when I stated "don't ask me where...." I meant tounge-in-cheek that I didn't want to admit how I "rigged" it to run. I know where I connected it, sorry for the confusion.  When the rain here stops, I should have an update.
 

Fuel Pump Relay - Help!

Reply #25 –
Either way , i agree with Tom  but its nice to hunt down the break in the feed, you cant assure yourself it isnt gonna start arching at some point in the future.  You can fix with a bypass but what becomes of the feed when it decides to cause other issues.

its your call, doign the bypass gets you going sooner with the odds of the least risk.  I would gamble on the bypass and just make a note to yourself in your EVTM drawing what you did.  a few years from now your going to forget exactly what you did and how.

I had to take notes on what i did to jumper the Neutral saftey switch on the Kia sporage, connector was under the dash about 3 connections upstream of the range selector switch down on the automatic 4x4, would have had to drop the trans to get it out.