Hello.
I have a 2003 Honda Accord LX 2.4L AT with 205K miles. When I turn the key to on, the cluster lights come on normally (the green key light goes out), but no crank and no start.
When I turn off the car, the green key light flashes five times..

Some backstory that may or may not be related to the issue at hand: A few days ago, I disconnected the battery and replaced both low-beam bulbs. During this process I dropped a wrench in the car engine compartment and used a magnet to retrieve it. Then I put the magnet in my pocket and it may or may not have been same pocket as my car key fob.
A couple of days ago, my wife (who has her own key) complained that her key fob buttons were not locking or unlocking the doors. I reprogrammed her keys and my keys for door locking/unlocking. However, My key fob did not take the reprogramming and stopped unlocking and locking doors. My keys will unlock the doors manually. I replaced the fob battery, but this did not help.
I cannot put the car in neutral using my keys, but I can put the car in neutral using my wife's keys.

My key status:
No crank, no start, key fob buttons non-functional, cannot put car in neutral. After Turning off engine, key light blinks five times. Green light does not persist when car turned on.
Wife's keys:
No crank, no start, key fob buttons do work, and can put car in neutral. After turning off engine, key light blinks five times. Green light does not persist when car turned on.

I was able to drive the car a couple miles to Home Depot, and then the start problems persisted.
The tow truck driver tried jumpstarting the car, but still no crank. I have begun to check some fuses like acg.
I replaced the starter a couple years ago, and the battery in 2021.

What should I make of the green key light flashing five times when I turn off the car? Could my start problems be related to the car forgetting my key's programming (or vice versa).
How would I know?
Any suggestions on systematic steps I could take to solve this no crank, no start issue?

UPDATE: Here are some steps /observations that I took to solve this issue with help from this communtiy:
1) Battery tested ok.
2) Starter is relatively new
3) Noted five flashing green keys from dash cluster when turning ignition off (0). No flashing green when ignition on (II). Shows key recognized by Immobilizer / PCM.
4) Checked battery connections for looseness/corrosion. Ok.
5) Used multimeter in resistance continuity mode to check all fuses. (probed top of fuses in place). All fuses had continuity.
6) Looked more closely at the starter and realized that a spade connection to the starter had come loose. Pushed in connector and car now starts.

Thanks.

Jon

 

Your key has 2 features that communicate independently with your car. The FOB lock/unlocks doors and can be reprogrammed to your car. The key battery only powers the FOB. The immobilizer is something different in your key that sends a code through a sensor to the PCM (engine computer). The PCM will not allow the car to start if the key is not recognized.. Reprogramming would require a scanner most DIY folks do not own.

Your description how the green key flashes is how the system works with the correct key, so you shouldn't have to reprogram the keys.

Start with the simple stuff first. Is the check engine light on? Can you check for codes with a scanner and post any codes on here? Does the gauge show correctly that you are in park or neutral?