My 99 honda prelude i just put in new battery. now the alarm keeps going off and car wont start. i have tried to turn the alarm off using the button on the car key chain but it wont turn the alarm off

I lost my key for my 1993 Honda Prelude the factory fitted immobiliser is preventing me from starting the car with a new key purchased by having one cut to suit the door lock can you please hel[p me disconnect or disarm it cheers Glen

Have you checked the neutral safety switch? The switch is designed to prevent the vehicle from starting unless the clutch is fully depressed. I am not quite sure where the switch is located, it may be under dash on clutch shaft or the transmission. Keep me posted on this matter.

Change the coolant sensor

check to see if the tps sensor is sticking if it does stick it will not let you throtle come bach to the rest point and will not let you start unless you push the pedal to the floor and hold it turn the key

It may be that you need to pair the alarm fob with the alarm as the battery can cause it to spike. Check the alarm fault diagnosis but with mine you just hold both buttons down on the fob for 5 seconds and it resets

if the battery is good and this happens, usually the starter is dragging internally, a new starter will fix this, starter normally comes with a new solenoid.

put gas in the car, take the key put in the car , turn it on without starting the car , turning the key on turn it off 2 times should start

Well, my mom found a little button underneath the dash board on the drivers side. And I guess its kind of like the reset button. So she pushed it and started the car and it was fine!

check for electric short.
if you have factory or after market alarm, that may be the cause.

Have you tried putting your Valet (original keys) into the ignition and turning it to the II position?