confusing, 1990 , CADDY a TOYOTA Escalade?
CHECK ALL FUSES in BOTH FUSE BOXES
all cars have huge options, and one harness.
so vast numbers of connectors are just there. ignore them.
seems... seems in science is no good, we work in absolutes.
or better valid ranges. (as a pilot says, "in the envelope")
ill try to answer both cars, the relic toy and 2000 CAD
we fix cars by diagnosis.
the first is to tell the helper what is wrong.
it dont start. (right?
and you check both fuse boxes, for blown fuses, right?
do you have spark? y/n? on all spark plugs.? y/n
if you have spark does spray in test fuel start engine
even for 3 seconds>? a key test.
yes, then you have low fuel pressure.
no, bad engine. (or you lied about spark , lol)
now fuel pressure.
the ECU can cut fuel and pump if it sees spark go bad
this prevents crash and burn,.like as seen on TV.
connect a scan tool is there DTC 340,355 being thrown cranking 5 seconds. yes, bad crank/cam sensors. or RPM is 0 cranking
bad ckp. senor.
so, rule 2, the ECU, many not, (READ FSM) run pump
until it is cranking
so you check for 12vdc at the pump cranking,
ok i got 12v
i then check fuel pressure with a real gauge.
it see 0psi, bad pump. see 10 psi bad pump or stuck open fuel
40PSI normal there is a range, but ask.
pressure reg. see 65PSI, fuel pressure reg stuck closes or return line blocked.
no guessing ,simple tests tools $80 total.
so does test fuel run engine> do that.
ever do a tune up?
ever check spark plug tips for wet or dry , after a failed crankup?
dry, no fuel. add some.
wet ,flooding.. crank using super secret WOT.
ok a direct quote from the FSM TOY.
- Using a jumper wire, short terminals FP and +B of the check connector.<< this is the diagnostic port.
- Turn the ignition switch ON, but do NOT start the car.
- The fuel pressure should read 38-44 psi (265-304 kPa).
- If the pressure is too high, the pressure regulator is probably defective. If it is too low, check for the following:
- Fuel hoses and connections for leaks or restrictions.
- Defective fuel pump.
- Clogged fuel filter.
- Defective pressure regulator.
now the direct quote for CAD FSM.
what engine,there are many?
rule 1 , 2000
ever scan the ECU/PCM for error cranking or must we do this the hardway.
pressure gauge on rule rail
not started engine.
is normal. (books shows scan too activate)
the FSM shows the leak down test too, at this port.
it also says using CAD scan tool command on the fuel pump.
says tool only allows 2 seconds run time,
but you can check it cranking or cranking then key
off see how fast 60psi drops.
there are many pump tests. and the leak down rate
and injector leak down test.
all this requires a fuel pressure gauge
and reading the tests on alldata.com or buy the full FSM from CAD.
Im sure the CAD only has pump power (12v) cranking and running
and running it drops about 10psi and rises at high altitude.
they wouldn't need
PUMP operation rules are complex.
this is all hard coded in the PCM brain this logic.
most cars are,
if sparks good, and not W.O.T cranking and cmp and CKP are
happen run pump and inject.
if not , cut fuel.
some cars cut the pump after 2 seconds running, its hard coded logic. if spark is bad.
many mech dont know this. but the only variace ive ever seen is
some cars do make fuel pressure. just key on,
for 3 seconds.
mostly older cars.
my guess you posted in the Toyota section?