If the transmission module goes, what problems does it cause on 93 accord"

is the speedo connected ??

the old 9-3 have a problem with the neutral switch,its mounted on the transmission and it tells the transmission module what gear its in ,if it goes bad,the module does not know which gear its in and will not allow the car to be driven.

Many vehicles have a control module for the automatic transmission called a transmission control module (TCM). The engine control module (ECM) communicates with the TCM to monitor the automatic transmission for faults. If the TCM detects a fault in the automatic transmission and sets a transmission related fault code, the ECM is informed of this also and sets a P0700 in the ECM memory.
This illuminates the Malfunction Indicator Lamp (MIL) to let the driver know there is a problem. If this code is present and the MIL (Malfunction Indicator Lamp) is illuminated that basically means there is at least one transmission code set in the TCM's memory. P0700 is an informational code only. It doesn't point to a direct fault in the engine, only a general fault in the transmission. More diagnosis is necessary to identify what the transmission fault is. This requires a scan tool that will communicate with the transmission module.

Symptoms Symptoms of a P0700 DTC may include:

• Malfunction Indicator Lamp (MIL) illumination
• The transmission may exhibit drivability problems like slipping, etc.

Causes More often then not, the cause of this code is that there is a transmission problem of some kind. The TCM detected the problem and set a code. P0700 means that a fault code is stored in the TCM. However this doesn't rule out the possibility of a failed PCM or TCM (unlikely).
Possible Solutions For a P0700 the only real solution is to acquire a scan tool that will communicate with the transmission control module. Extracting this code from the TCM will be the first step in repairing the fault in the transmission.
If the TCM compatible scan tool will not communicate with the Transmission Control Module then that is a good indication that there may be a fault with the TCM itself.

"Limp Mode" is determined by the Powertrain Control Module (PCM). It could be going into limp mode as a result of a transmission malfunction or it may be going into limp mode as the result of an engine control problem. The only way to find out is to scan your onboard computer system and retrieve any engine or transmission fault codes and diagnose and repair accordingly.

Please note that engine control problems can CAUSE transmission control problems. If there are any engine control faults, these MUST be diagnosed and repaired FIRST.

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If you mean the S light is flashing, then your transmission control unit is telling you there is a problem somewhere. Click here to learn how to diagnose the problem. That link is for 92-93 accords where the D4 light indicates TCU errors, so just replace every instance of "D4 light" with "S light".

usually the problem is the TCM or transmission control module. They are known to go bad. If transmission is working ok then this is most likely the problem.

its kind of hard diagnosing this kind of problem like this but i could tell u what it might be. it could be your TPS sensor. shift solenoid or something wrong with the transmission valve body. i hope this helps i love those cars : )

The computer for your transmission is bad. This is a common problem on the 90-93 accords as I have replaced three of these on three different cars. It is located on the passenger side floorboard under the carpet where it goes up towards the dash. There will be two computers and it will be the one on right. It is an easy change but make sure the numbers match your original one. The first one I changed didn't have the same numbers and it worked fine but my D4 light stayed on. I hope this helped.

replace the speed tranducer, located on the gearbox

I had a similar problem on my 93 Accord after I accidentally threw the car in reverse at 50 mph, obviously wrecking the transmission. When I got it rebuilt I was told the transmission pump was to blame (clogged with "shrapnel"). I, and your car manual, recommend taking the car in to get the tranny looked at. Especially considering you just had the fluid changed which is what would normally cause the problems you are describing.