repair code "5 4 2"

this code hase many different

descriptions online.

now its' secondary circuit open.

live in michigan so the chassis

grounds are all suspect.

6v at pump, 6.82 on manifold.

12.76v across battery.

anyone a step-by-step w/

pictures to show the fuel pump

circuit test? 1994, 302 auto 4x4.

somehow the site accepted this.

t.i.a.

Trouble code 542 during self test indicating the Powertrain Control Module (PCM) is not detecting a ground through the fuel pump monitor circuit.

At the fuel pump, check for power on the Pink/Black (PK/BK) wire when the key is turned on. If there is no voltage there, check for a open inertia switch.

If voltage is there, check the Orange (O) wire for ground. If the ground is OK, replace the fuel pump.

Seabronc posted wiring diagrams here recently; from a 95 EVTM but are the same.

see #4 for those wires @ pump

and by our pal BroncoJoe;

" took a look in my Haynes manual.

They list 10 separate grounds... A-J.

A. Starter mounting bolt

B. Right front of Engine compartment near the battery

C. Lower left front of engine

D. Right front of engine compartment on upper radiator support.

E. Left front of engine compartment Upper radiator support

F. Bottom of cowl panel

G. Rear of left fender apron

H. Behind bottom of right cowl panel

I. Left rear corner of cargo area near rear lamp assembly

J. Under center rear of vehicle on rear cross member.

and by Steve - he shows a diagram of connector #C441 for da FDM (fuel delv. module = pump)

ou can open it & ck for that Orange wire Ground - both ways

thanks for your reply. today i tried

to jumper the fuel pump relay, but

don't have voltage here. have 12.7

volts at the f/p fuse. how do i dis-

assemble the power distribution

box w/o breaking it? sorry for the

dumb question - so far the lock

tabs have broken on every

connector i've tested.

94xlt said:

thanks for your reply. today i triedto jumper the fuel pump relay, but

don't have voltage here. have 12.7

volts at the f/p fuse. how do i dis-

assemble the power distribution

box w/o breaking it? sorry for the

dumb question - so far the lock

tabs have broken on every

connector i've tested.

Click to expand...

ok, np

looking down at PD Box, there are 4 plastic clips on both sides; need 4 hands...and 2 to 4 small flat blade screwdrivers to gently push each tab's inside each "plastic clip" Outward

then there is small plastic rectangultar piece on driver fender side to lift cover up; hinge is on engine side

Diagram in a 93 by rob

Diagram in a 96

Source: by Roadkill our pal!

btw you can Swap the FP realy with Horn Relay in 92-96 to Test FP Relay ...

Cover up pic by froggman



also, I need to get my Ford CD back soon to see that other relay box to da right of the PD Box... it opens up by pressing tabs outward using fingers. one relay in there is same pn and type to all other relays in PD box It is called the Trailer Relay Box.

from Ford CD; PCED;

"...Fuel Pump Circuit Operation

When the ignition is switched to the ON position, it turns the EEC Power Relay on. The EEC Power Relay provides power to the EEC-IV processor and the control side of the fuel pump relay. Power for the fuel pump is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flow is through the fuel pump relay and Inertia Fuel Shutoff (IFS) switch to the fuel pump. The IFS switch is a safety device used to shut off the fuel pump in the event of a collision. If the IFS switch is "tripped," it must be reset by depressing the white or red button on the top of the switch. The fuel pump relay is controlled by the Powertrain Control Module (PCM).

When the ignition switch is turned to the ON position, the fuel pump will operate. If the ignition switch is not turned to the START position, the PCM will shut the fuel pump off after approximately one second. The PCM will operate the fuel pump when the ignition is in the START position to provide fuel while cranking.

After the engine starts, the PCM will continue to operate the fuel pump unless the engine stops, engine speed drops below 120 rpm, or the IFS switch is "tripped."..."

PUMP VOLTAGE CHECK

"...l Key on.

l Ground the fuel pump lead of the Data Link Connector (DLC) with a jumper at the FP lead. Refer to Electrical and Vacuum Troubleshooting manual for vehicle if it has a different connector to locate position of FP lead.

l Use VOM to check voltage to fuel pump. Check for approximately system voltage at the fuel pump connector, fuel pump relay, VRCM, or IRCM, whichever point is accessible and closest to the fuel pump. (Electrical and Vacuum Troubleshooting manual may help in locating these connections and components.)

l Is fuel pump voltage approximately system voltage (12 volts or better)?

Yes

CHECK fuel pump ground connection for tightness on vehicle and at fuel pump external connection. If problem found, SERVICE. If no problem found, REPLACE fuel pump assembly. GO to

thanks to all - i only got this

far by reading the archives.

i'm back in the engine

compartment. 12.7v at fuse

-0- at relay. i need to access

the feed wires w/o breaking

anymore plastic tabs.

miesk5 thanks - i have the

4 screwdrivers - its just the

tabs want to break. got

battery voltage at #37 now

the problem i'm having

since the color codes are

not the same online, nor

in chiltons, nor f.f.i.

i guess i'm looking for a

proven methodogy.

right now i have batt

voltage at fuse - none at

relay socket.

the 12v signal and 6v

signals - i don't wish to

fry any ecms. thanks.

12.7v at fuse

-0- at relay - ck FP relay socket for corrosion; I use anything small enuf to fit & dip in and pull out to ck; such as plastic tooth pick; Ive been cking and removing corrosion from my 4wabs HCU connector

battery voltage at #37 - 37 at FP relay? or I guess EEC relay from what you wrote following this; if so, then EEC is ok, as far as it's EEC relay operation.

now the problem i'm having since the color codes are not the same online, nor in chiltons - how about Seabronc's diagrams in Link above