ST wont power ECU or start but power to everything else

[obswholesale]

so parked the car... all worked fine...
stopped at autozone to get a replacement headlight as one was out

came back .. replaced the headlight go to startthe car.. NOTHING
power to everything ..lights... windows..BUT
no pump... no ignition .. no starter..

hook up scanner...
NOTHING .. no communication to scanner at port .. no crank ..

jumped starter relay to check starter.. turns over.. but no fuel pump

changed EVERY fuse and relay... all check out and work as should.. EXCEPT no ecu power.. no pump .. no crank

whats up ?


Model: 2004 ford explorer sport trac
Year: 2004
What have you tried so far?: changing all fuses and relays.. jumping out starter to make sure it cranked

the relays under the hood do click like the are getting a signal when you turn key fwd to run/start





with scaner connected there is no signal from ecu and scanner "will not connect"

when I jumped out the starter relay the truck turned over
The fuel pump does not come on and the data port will not communicate with 3 different scanners I tried

I'm guessing the computer is controlling the pump and with out the computer nothing happens

If all fuses are good what would stop the ecu or data port from getting power

The cig laughter works also

 

[waskly]

does the dash turn on? does the check engine light illuminate?

does the pats theft light flash rapidly?

did you remove / disconnect the battery while at auto zone to replace bulb?

what engine 4.6 or 4.0l?

 

[obswholesale]

does the dash turn on? does the check engine light illuminate?

does the pats theft light flash rapidly?

did you remove / disconnect the battery while at auto zone to replace bulb?

what engine 4.6 or 4.0l?

yes dash lights up fully as it should
theft light lights up and flashes
at first i did nt disconnect the battery ... never did before
after about an hour changing fuses. i did discon the batery and reconnect
still same

4.0 engine

 

[swshawaii]

Fuel pump inertia switch?

http://www.explorerforum.com/forums/showpost.php?p=2572870&postcount=3
http://www.explorerforum.com/forums/showthread.php?t=298746&highlight=inertia+switch

 

[obswholesale]

does not explain why scanner wont connect to ECU

 

[swshawaii]

does not explain why scanner wont connect to ECU

Apologies, I overlooked your TITLE. Also, the engine will still crank with a tripped inertia switch. GL

 

[waskly]

yes dash lights up fully as it should
theft light lights up and flashes
at first i did nt disconnect the battery ... never did before
after about an hour changing fuses. i did discon the batery and reconnect
still same

4.0 engine

how fast is the theft light flashing?

 

[obswholesale]

how fast is the theft light flashing?

steady pace
with moments of not flashing

but its flshing the same overallpace as when i am sittingin the car key on engin off... or engine off before i get out and lock the doors

 

[waskly]

steady pace
with moments of not flashing

but its flshing the same overallpace as when i am sittingin the car key on engin off... or engine off before i get out and lock the doors

ok is the check engine light on when you turn they on, also is the odometer reading mileage or dashes?

also does the vehicle have an alarm?

 

[05dakotatrac]

i know its a long shot but can it possibly be a bad ground? the engine sensors tend to share grounds then have a final chassis ground before going back to the battery.

 

[obswholesale]

guages show miles... not dashes
yes check engine light is lit up when i turn key
an nothing happns

 

[obswholesale]

so here is the update

i had roof lights installed on my ST

the mechanic tapped the 10amp fuse that feeds the data port and ecu main feed line
the fuse was not seated properly .. and the roof lights caused a drop in amps
hence the line shut down as a safety for th ecu

all fixed and working now

now to find out why i keep kicking out a cyl 4 misfire

 

[scott2794]

I have a similiar power problem. I am getting dashes on odometer instead of mileage. Any suggestions?