1997 vw jetta will not start after battery disconnect

The first link says you can disconnect the battery cables and touch the Pos and Neg leads together to discharge any stored charge in the system. I don't think that is good, it works on some cars and other cars it can short out electrical components. I think it is better to disconnect the battery and turn the key on and let it sit for more than 1 hour to reset the immobilizer. Just my thought.
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Connect the battery and press the button on the key fob. If that does not work, try starting the car.

all vw MUST be reset after battery dies/changed.put key in door,unlock/hold key over 30 secs(windows go down)then lock/hold key over 30 secs(windows go up/sunroof closes)then press unlock button on remote for 30 secs......RESET DONE......(try this for fun....sit in car after turning off engine/remove key,drivers door keypad is still live(until you open door)ALSO when engine is running lower any window and then raise up with fingers in top of door,the window will rollback.(if you do it once it hurts..twice it really hurts..three times it traps your hand in.)ALL THIS is NOT in the handbook.......

SORRY TO TELL YOU WHEN DISCONNECT BATTERY ON VOLKSWAGONS.YOU MUST USE A MEMORY SAVER.IN CIGARETTE LIGHTER.TO KEEP COMPUTER MEMORY.IF YOU DONT.YOU HAVE TO GET A SPECIAL SCANNER TO REPROGRAM CAR LIKE THE DEALERSHIP.

You'll need to disconnect the high and low pressure lines from the compressor. Unplug the electrical connector for the compressor. Remove the belt. Unbolt the compressor from the motor. Reinstall, connect a vacuum pump to the high side A/C fitting, start the vacuum pump, run pump until to have about 15psi of vacuum and then disconnect the pump and refill with refrigeraint.

Reconnect starting with positive then negative.

If the mass flow sensor was bad, the check engine light should of came on giving off an engine code. To remove the mass flow, disconnect battery neg cable, then pull of the wire harness and pull out mass. You will probably have to remove the air intake hose.

remove and have the starter bench tested

My friend you are faced with a catch 22 problem. The first thing I would like to know is, who installed the alarm system? Did you do it or was it professionally installed. If it wwas professionally installed I would go right back there and discuss the problem with them. It very well could be a defective unit. If you did not have it installed professionally I would disconnect the alarm and see if your battery still get's drained.If so, then the alarm is not the culprit, and you have some hunting to do. If not then you have some testing to do.Next what type of alarm is it? Try to google it. You may be able to find a trouble shooting guide to assist you. I know that you said you just replaced the battery, but the alarm very well may not be the culprit. It could be many other things as a loose fanbelt, bad diodes in your alternator, or some other componet draining your battery.

It might be starter wiring problem. Look for wire coming to the top part of the starter. One might be not tight enough or went off.
Good Luck
for a 1997 Volkswagen Jetta