Ignition module, crankshaft position sensor , PCM - engine computer etc... your best bet is to take it to a ASE certified repair shop or the dealer > You have no idea of the complexity involved in the computer systems on this vehicle ! unless you want to replace part after part an not fix it !
Try to say wont crank
or
cranks but will not start
its 2 different systems where,
cranking
and
EFI.
so guessing is fail.
the IMMO does not kill cranking (Skim/SKIS)
nor does , pesky, ASD relay.
but have friend crank, is the starter relay pulling in (click.clunk)
if yes, the PCM is happy and the relay (may) be good. if the relay contacts are burned it can pullin and fail. replace it.?
i use a volt meter on all 4 relay pins
11v,11v,11v and 0 (0 is pcm permission pin)
if this passes, i go to the starter
so next time it dont crank
you hot wire the starter. with jumper wire or old screw driver
keys on pocket.
battery lugs clean.
the battery is always #1 suspect, not starter.
starter last 3 times batteries....so...... jumper start with cables was first and not done. fail
hot wring the solenoid. on starter
it cranks every time, (say)
well that is key line failure, not starter.
see?
just one test and we know.see its not a computer.
i have the fsm and same car
i have the real book.
if you need drawings, ive posted this over 200 times here
no lack of examples for jeeps ,no crank or cranks ok,nostarts
the transimssion has switches.
the PCM reads them if wrong, kills the starter relay. not scanning, now, you missed the BOAT.
these P/n?switches can fail. that block the key line, aka/ PRNDL switch.
.
if you can read the fsm page on cranking
its very very simple.
.
the WK
http://www.morris4x4center.com/knowledge-base/index.htm?utm_source=cj#service
seethat?
see chapter 8w? (wiring)
see the starter and that very very simple single wire. and relay, and pcm logic.
to the tiny starter lug? (spade)
bingo
also the battery ground needs to be good
not loose
not attached to the wrong place.
that is why AAA hot jumper cable tests work so well
he does so and its dead
he hot wire it, its dead
omg loose battery lugs. or connected wrong.
or green lugs.
i answered ONLY for NO=CRANKS.
11v is typical live cranking voltages.
if you had a voltmeter, and it dont crank
the answer in 5 min work , why.
that is why Gawd invented this $10 tool
to end blindless to electrons.
ask, its super easy....
again a voltmeter would have show
2 things, weak battery and dead alternator.
we cant discount the new battery
why? ,he drove to store,and charge system
was dead, battery can be week.
and battery can self recharge, ask why.
(called, localized discharge... acid batteries..do that..)
lean to hot wire the solenoid
can be hard to reach, i cus jeep
see this
see small lug, keys in pocket, in park
jump tiny to huge outboard.
crank now? bingo a good starter and a charged battery you have.
http://www.fixkick.com/nostart_files/the...
or herehttp://www.fixkick.com/starter-hotwire.j...
the engine cranks but will not start
cuz, ECU is off line, keyoff.
btw ,no starts, (cranks)perfectly
is lots of computer actions there
the key line (and trans switch p/n)
has a relay
that can be bad, and 20x cheaper that the bat/starter. new
20x
of PDC FUSE 10 LOOSE, OR CRACKED.
SEE WHY VOLTMETERS WIN> oops 12v one side 0v other on fuse.= bad
THE RELAY GETS POWER FROM the key switch.
to relay coil top
THE PCM DECIDES IF THE RELAY is allowed to. pull in.
that means step one,after fuses,
we scan the pcm for errors
for sure a/t transmission errors
and x10 that any trans shift selector errors.
there are errors in the PCM that can blockcranking.
as in most cases, not scanning pcm first
you lose
same with fuse testing
or if not up to that, the relay swap.
short answer, as always
tell me the voltage on all 4 pins of relay
cranking and failing,and i tell you why.
in some cases the pcm might even say
DTC error, start relay dead.
the ASD realy does that, too. (nostarts )
the PCM energizes it, then checks its output
if wrong, it reports it.
not looking , is the fail.
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