Hi dears Toyota corolla 1994 4A-FE i want to know what are things that the ECU checking before send the negative to Fuel pump relay the fuel pump works while cranking and also by connecting B+ and FP

no country told vast Corolla exist, not the same on world stage.

which engine size sold world wide. 1.6 or 1.8L: seen in USA?
GEN 8 Corolla it is.but was delayed to USA intel 1997 so is not USA car? no country told. or is not USA or not 1997 car.
1ZZ-FE?????? is chain drive cam. if your unstated engine is cam belt drive(as is ours) it is now bad. that belt. and timed all wrong now. E110 model had 12 engines world wide.8 were Petrol spark.
or USA car is belted cam, so if have that the belt is bad.
causes Spark timing to fail and when spark timing fails so goes fuel.dead.(ecu logic rules all)
we test fuel pressure using fuel pressure gauge at the fuel rail while cranking, (not dribble tests) pressure must be at spec or it fails.
spec means OEM factory specifications stated in the service manual for all cars made, only this matters. (fuel) answer is generic.!!!!!

1. :check all fuses first. yes spark and fuel yes.
2. USA cars 1996 scan he PCM for errors.
3. if said can show P03xx error or spark lost there will be no fuel allowed to flow by law. (no crash and burn logic ECU)
4. if engine is belt cam drive, as ours is the belt fails at 60-100k miles and slips and all timing of cam and spark are lost. making fueling Impossible so we check this first.
5. each of the 8 engine tests are unique for sure fuses EFI and all of that.
6. if x4, engine compression is below 150psi the belt is bad. cam.
7. if a spark timing light shows spark dear or way off time belt slipped. or on some 96s, the distributor is bad,or molested..
8. if all seems good we check fuel pressure last cranking,

no E110 version of this car told, and clearer seen here.
the vast variances world wide

https://en.wikipedia.org//wiki/Toyota_Corolla_(E110)

There is a relay. Its mounted with the EFI ECU in the right kick pannel. The ECU controls the relay via a ground in the computer and turns on the pump for cranking and for when the engine is running. The relay is almost never the issue. Check the fuel pump wiring at the tank and the fuse for the ECU and fuel pump.

the car is really a Toyota, but the real question is did GM move it.
that makes it harder.
http://www.toyotanation.com/forum/16-archived-corolla-threads/9068-geo-prizm-toyota-corolla.html

off all questions ,locations are the hardest.
many books dont say, because the makers love to move parts around.
the only book that gets it correct is the FSM. why not get one.
and keep it with car. so you dont have to get help for every page.
and hark some cars there is no seperate Fuel pump relay.
its part if the ECU main. common on some 1990 Geos.
my first question is why do you need this?

my online page shows?
Fuel pump relay is located at the lower left side of the relay box - fuel injected engine.
i dont trust online , for older cars, they mix, parts up badly (SSDD)
and i look more and its a mix of metro's and nova/s ,trash info.
i cant even find a schematic, which is what i look for first.
to see the relay and now it REALLY works, and not assume i just know.
im looking in toyota online now (Geo docs are iffy, at best GM)
find a real GM GEO used FSM off fleabay.

4A engines, the relay is called C7 "circuit opening relay"
has 5 pins and forms mag. "OR "logic inside.
the relay closes for CRANK "OR" ECU happy.
ECU happy means , spark is ok "AND" engine is running. pin FC on ECU.
now 7A, its the same, i never assume it, i look

found it , this car has no less than 6 Junction boxes. relay and fuse.
4 in engine bay if ABS car.
and 10 relay location drawing.
why not look on line at alldata.com and see them.
JB2 is the box. in engine bay, left strut tower. (usa drivers side)
they have EFI main relay
and one more called engine main, with 5 pins.
so its not even called a fuel pump relay, hard to find.

jb2
facing box.
see top row off relays
and bottom row of fuse.
so left to right is. (not canada , only uSA)
horn--radfan1---EMR---headlight--EFI main,

so EMR is fuel pump.

alldata.com
i found it under toyota corolla, 1993.
if GM does this diffr, i dont know, get a real GM book.

It's behind the console, in front of the gearshift on the ride side (not the big flat one, that's the ECU) but it's not called a Fuel Pump relay:

The fuel pump relay is located in the fuse box drivers side of fuse box

4afe or 7aFE engine?
as always for ever and ever, check all fuses.
check it cranking some ECU dont power pump until cranked.
the ones that key on power are 3second, can you run that fast?
no. so crank.
if the fuel pump relay closing and sending full 12vdc to pump wire.?
no?
then fuse is blown
if cel lamp is not on key on fuses, are blown or lamp or ecu bad.
fix lamp first it must glow, that glowing means ECU passes, basic self tests. (like a pc doing P.O.S.T) (i rebuild and tune ECU's)
do you need a schematic,(alldata.com has it)

books are amazing things, no? im looking here, seen it many times.
the magic fuel pump relay on the 4AFE.
it is really a 2 coil relay forming what is called logic "AND"gate
7a works same,.... just looked
the ECU enables coil A with LC command line (software) 0v here.
the main relay must close and 12vdc out to pump relay
then the driver cranks, and relay coil B is activated. and pump spins.
always crank and test. see why?
if you need bigger photo ask, .....
if the relay fails to close cranked, check that the crank
signal makes it to (12v) to top left coil below.
if not there will NEVER be fuel. see crank sig below in red.

when u checked this u do realize the fuel pump only has 12 volts for 1 second then the computer turns it off unless the engine is started? let me know.

keep in mind, just because the ignition is on does not mean you going to get power to the fuel pump, 1st make sure you fuse and relay are good, next disconnect connector plug from the fuel pump and take a 12V light tester and connect to the connector plug positive and negative, than turn the ignition/crank engine over and see if your 12V light tester lite up, if not than you need to check the crank sensor making sure is not faulty. what the crank sensor does, it sense the flywheel turning and send info to the ECU, than the ECU send power to the pump turning it on and keep it on as long the flywheel is turning. if your the sensor is bad, the ECU doesn't know if the flywheel is turning, in this case the fuel pump will get no power.

No, Toyota Corollas don't have an inertia switch, that is mostly a Ford thing. Check to see if you hear the fuel pump run when you turn the key on. Check the fuel pump relays, fuses (EFI relays and fuses) or might be the fuel pump itself. If it does run, there might be some wires that were disconnected or displaced upon impact.

I regret to tell you this, but, the whole truth is: Taking out a diesel and installing a 4AFE will require you to change the entire engine room wiring harness (including the fusebox), the proper 4AFE (manual or auto trans ECU), the fuel pump and the fuel filter, the air intake system, and most def the dashboard harness (which also connects to the ECU). What you have here is 2 entirely different worlds, gasoline vs diesel.
Sorry.
I would not recommend you to undertake this job, unless you have a complete "donor" vehicle for the abovementioned parts.