What exactly is limphome mode and what diagnostic test needs to be done or scanned???

endless same posts here, forever. 20 _+ years, Eboxs
same answers.

1. levels ATF wrong, too low or too high, hot engine'+park
2. automatic transmission i guess, never said PRNDL drive ,reverse or low
3. 2nd gear A/T is limphome mode.
4. all fuses good.
5. scan the PCM see TCM DTC errors bingo?
6. lots of causes, and tests, even tranny pump tests in the service manual.

check all fuses. why not? costs nothing .
or RTM
https://eautorepair.net/Marketing/Default.asp

read the manual
next is scan the PCM</TCM at the USA? OBD2 16PIN PORT.
IF THE TCM STORES ERRORS. (I BET IT DID)
MANY MODERN CARS THE TRANSMSSION GOES TO LIMPHOME MODE TO SAVE ITS OWN BACON, AND MORE.

SCAN IT, DO NOT DELAY SCAN IT.
YOU DO OR THE SHOP DOES, TOSS COIN, DO IT.
1: CHECK FUSES
2: CHECK ATF LEVELS PER THE BOOK DO NOT GUESS,DONE HOT ENGINE,IN PARK. PER MANUAL.
3:SCAN IT, NOW. POST ERROR FOR HELP.
4; DO THE PRNDL PRESSURE TESTS IN THE MANUAL (A TOOL)

2003 if car has TBW, TAC, if the scan show sTAC failures
the PCM goes to special limphome mode. FOR THROTTLE error
s
I guess car has no tachometer? to see the transmission fails to upshift, 4 times at least. 1,2,3,4 ,RPM drops from 2 to 4.
all A/T DO THAT, ,NOT CVT . (Some CVT even have steps to make owners happy, but are useless. in fact,

only clue is screaming, well that is stuck in 1st gear and is tranny limphome( it has its very own limphome mode too)
check all fuses. and scan the OBD2 scan port, next, or go broke guessing endlessly or even putting wrong parts in to car or done wrong..
you can not fix modern cars lacking a scan tool, no way.
talking drive train or ABS. etc.
almost 20 years old and has lots of problems ignored,
which one to fix first is a hard choice that many.

is REVERSE OK
is PRNDL ( is L okay)???

OK what is the correct order to test. for sure not that
the service manual covers that, for sure the TCM.
1: ;all fuses good ,every one.
2: next is scan the PCM why skip such a key step> here??????
what if speed sensors fail.?
what if load modulater fail in the box.
the transmission book there and ATSG books tell you that and tells you that pump pressure test ports must be at spec or upshifts fail.
if pressure is low (or vast reasons) it can not fully operater the 2nd gear Servo piston to do so,

see my crude drawing her. (older tech box but works same in principle.
do you know what Limphome means for engine and trans?
on the trans, the TCM brain see horrible errors ,(you ignore)
and goes to limphome mode on the box. just 1 year or 2,
depends on actual box model like 4L60? GM box.there?
not sure I will look it up. not saying I know all Limp modes on all boxes.
below the shift lever is now a bank of shift solenoids
but they do the same thing.
if pump and its regulator work and filter not packed up or sucking air
the pump will have spec pressure at idle and the stall load test
the speed sensors must all work and no P07xx errors allowed
even some engine fail can set the trans to limphome too.
the FSM covers that (factory service manual)

ahhhhh you have this transmission same as my wifes GC2010
4 Door; 5-Speed Auto W5A580 Trans. aka NAG1, and 722.6
I have full manual books on it. but not your TCM
or it has this box
42RLE

learn to decode your VIN and see what trans is there first.

and scan it. next after fuses.
The scans see it all, engine and trans both.
and must never be ignored.

bingo its in limphome.
the lamp means (as the operator guide tells)
get it service, hark?
in limphome mode, the Ecu/PCM CAN GO REAL RICH FUEL
This can burn the cat to H3LL
are you DIY, not stated
the FSM says, to Scan IT, GOT A SCAN TOOL?
SCAN IT.
see those DTCS,
each has more tests, ask. or read ASE books on DTC tests.

no man on earth can guess your DTC errors,not now,not ever.

automatic.?
scan it , the TCM may be in limphome mode
and most transmission will skip a gear.
scan it, no scan it twice.
the DTCs tell you what tests are failing.
dont miss any.

2001 Esteem
A/T tranny.? 4speed?
(check fuses yet?)
this transmission shifts via the TCM electronic brain.
and will throw (store, or live) DTC errors.
IN USA all these cars are OBD2 compliant and all scan tools
work here, you plug it in , and drive and see if there are TRANNY
DTC errors. all cars 1996 and newer, do that. (for sure Suz)

these errors are covered in the FSM and tells you what tests
to do , to isolate (and diagnose) what is wrong.
in and out.
what does that mean.?
to a false neutral? or to 2nd? what?

btw2, the TCM on this car also goes to limphome mode.
when certain DTCs are set. and will skip gears at that moment.
my suz,, both skip 2nd gear in limphome mode.
The TCM needs good inputs or it can't work right.
it has many inputs.
shifter switch PRNDL.
VSS1, VSS2 (veh,speed,sensors)
TPS. (throttle angle.)
ECT. (engine heat)
btw3:
this trans, 4speed, you can do the unplug test on it (FSM)
and it works like a manual transmission, see the FSM for how to do that, this test proves the trans is ok, and the TCM is cause or its inputs are bad.

which engine.?
is the CEL glowing running (check engine lamp)
yes, why are you ignoring it, scan it.
better, scan it any ways, and not all errors glow the CEL.
sounds like its either:

1. check all fuses
2. ECU stuck in limphome mode (yes, scan it)
3. misfire, not doing tune ups. at each 60,000 miles (100km)
4. bogging starving for fuel (tests) fuel pressure is #1 test.
5. bad fuel.

yes, scan it, why wait.?

no available code reader.?
you need to buy a car that has no PCM.
like 1987 or older xxxxx car...
you can not fix cars without a scanner. not today.
buy one, rent one, barrow one.
it seems your's is in limphome. mode.
get the FSM and read the trans chapter.

the 42RLE is electronicially shifted, the E on the end tells us that.
and has TCM. transmission control module.
The TCM , today is usually hiding deep inside the PCM .
The TCM can not shift (just like all computers) if the inputs are wrong
or the TCM discovers gross transmission slip.

if the Tranny slips. the out put shaft sensor never reaches.
the correct RPM (speed) and the TCM drops to limphome.
Limphome is a mode that allows some usage,
after all , its dead. the system that is.
as always, elect.
check all fuses (test them) (alldata.com tells you which ones) or the FSM.
then check level using the correct procedure, do not guess.
if you guess and overfill the tranny , you risk foam up and bearing starvation and (destruction)
THE FSM the factor service manuals on all cars have this chapter
called how to fix the tranny in car, or on car tranny service.
we read that and see many simple tests. we do them.
the first checks are SCAN TOOL.
then stall test.
then pump pressure tests.

we do that tests and gather all evidence we can , and then
do tests, totally based on those facts and the facts stated in the FSM
related directly to the DTC errors you are blind to.

there is no way to cheat this process. other that, get the car serviced.

Replace maf sensor