What is the tcm manual shift - 1999 Honda Accord

NO TRANSMISSION OPTION TOLD AT all, your RPO list tells that..
or which engine of 3 sold new. tranny matches engine torque !
AUTO 4L80e?
manual trans NV4500;?
only clue told is won't shift
not told is auto shift fails or the shifter lever NV4500;, is dead.
the 4L80e is Tcm electronically shifted
and all USA cars this year we can scan the TCM for errors
and I bet dollars to donuts it has tranny errors.!!!
get the service manual and see how to scan the TCM.
no better way exists.
1996 up is OBD2 compliant (USA only)
some the PCM has TCM brain inside and DTC P07xx errors show up using any scan tool, but RTM

If the TCM detects a transitional state between D2 and D3, then DTC P1822 sets. DTC P1822 is a type B DTC.
The transmission manual shift shaft switch assembly is a sliding contact switch attached to the control valve body, within the transmission. The four inputs to the transmission control module (TCM) from the switch indicate which position is selected by the transmission selector lever. This information is used for engine controls as well as determining the transmission shift patterns. The input voltage at the TCM is high when the switch is open and low when the switch is closed to ground. The state of each input is displayed on the scan tool as IMS. The four IMS input parameters represented are Signal A , Signal B, Signal C and Signal P (Parity).
DTC P1842 sets when either of the following conditions occurs:
• The TCM detects an open in the 1-2 shift solenoid valve circuit when HSD2 is commanded ON.
• The TCM detects a short to ground in the 1-2 shift solenoid valve circuit when HSD2 is commanded OFF.

Conditions for Setting the DTC
DTC P1843 sets when the TCM detects a short to voltage in the 1-2 shift solenoid valve circuit.

You have a short in shift solenoid bring down the Five volt reference circuit of the ECM - engine computer .
P1639 Cadillac PCM 5 Volt Reference Voltage Circuit Condition Couldn't find this DTC listen in the factory service repair manual . Your vehicle doesn't have a PCM , your vehicle has two separate modules . TCM for the transmission and ECM - engine control module .
How to check the 5v reference circuit for short to ground Cadillac

You will need to reset the computer, find reset button or disconnect battery and cycle through the start and shift process, then leave disconnected, overnight if possible or at least 2 hours, before reconnecting, start and let idle for 5 minutes before shifting to drive, then drive car on open road and give a firm push to the throttle, try manual shift, if no go, inspect tcm.

automatic transmission, right?
dont shift , impliese but fails to say, by whom.???
on mine a 5speed manual stick, it can't shift by many a way.
ill take a wild guess and its an A/T
Don't shift.

ok, now I scratched head, do you mean
it stuck in 1st gear.
or did you mean its slipping , and feels like in neutral at all times.
or skips gears?

during these early transitional years, they had 2 transmissions
the newer one is electrically shifted.
and going farther we need to know what trans is really truely there.
we are blind here and cant see what you have.
if your car is a TCM shifted tranny (TCM is tranny brain,puter)
it has scan codes. so dump the tcm error codes.

http://geometroforum.com/topic/5011680/1/#new

or log into alldata.com and read the TCM page.
its not a secret , all metro FSM cover this.
fsm means , the Factory service manual. get one.
or log in.

maybe its not the TCM. ? ( it has a learn mode, but may be it cant do that because the trans is bad)
did you read the FSM on
ON CAR A/T tranny tests?
if not why not?
http://hondatech.info/downloads/Auto/Manuals/Accord/

did you replace the A/T pan filter? if clogged the main pump will be weak and will never shift.
in the FSM it shows, you checking the main pump pressures.
did you? its one of the first tests.

why not ask installer that.
btw , the TCM can fail and do that.
that is either a separate module or part of the PCM.

The TCM does all shifting. electronic, shifting it is.
the TCM has scan code errors, did you scan it and the PCM for errors.
if not , why not.????
2>3 shift failure.

even a loose or corroded , trans wired connector can fail.
or the tranny ground strap is missing.
saw a guy replace a tranny 3 times. and all 3 times failed.
he never knew the trans must be grounded perfectly .
his was missing, others simply broken, others rotted away.

what we do is make sure the TCM is sending the correct
voltage single 0v.12v, etc. to the transmission solenoids.
if not, the TCM is bad, or is in limphome. or inputs wrong.

TCM have what is called limphome that can skip gears.
my 4speed skips 2nd , in limp, by DESIGN !
all this is covered in the FSM, why not read it.
or look at alldata.com it's there too.

i also have a switch box, i made., that attaches to the tranny
allowing me to make a manual transmission,
if that works the tranny is good.

the TCM will in fact mess up if its inputs are wrong
just like all computers do.
inputs are, TPS, VSS1 , VSS2, engine heat. shift selector switch PRNDL , and others.
The TCM shifts by the state of inputs. period

one cool thing, some cars pre 98, or so
the TCM is separate box. and with it unplugged
the shifter is now a manual transmission car. (for test or?)
have friends driving like this for 3 years.

Sounds like you may have fried the tcm I would go to car-parts.com and get a good used one. You could check and see if there is any fuses that you blew out that control the tcm if you have a manual for the car you can look at a wiring diagram and find out what fuses are associated with the tcm if not check them all.

TCM stands for Transmission Control Module.
It is a firmware programed device designed to control the shift points of your VW's automatic transmission. It is also responsible for safeguarding the transmission against abuse or other damaging problems from the operator as well as the engine. For instance, if you were driving down the interstate and accidentally bumped the shifter into reverse. the TCM would "see" that you are traveling at a high rate of speed and reverse was selected but nothing would happen. Or, your engine is misfiring, the TCM may only allow certain gears to be used to avoid you stalling in the road.
When a TCM malfunctions your car may not shift into overdrive, or in worse cases may not shift at all causing you to have to shift the transmission manually.
Most late model automatic cars have a TCM.

This is a very common problem, the transmission computer (tcm) has gone bad. It is located under the front passenger footwell. Pull back the carpet and you'll see both the engine computer and the tcm. They are available as rebuilts on ebay and other sources online. Do not buy one from a 2nd hand supplier. They are all bad and must be rebuilt. Google: "accord tcm" for more info.

I have a 1993 honda accord and my clock won't keep time,can you help