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2003 ST4s No Crank

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Hi everyone, I've been riding my ST all winter with no trouble but Saturday I decided to give her a bath and now I get nothing when I press the button.

I bought her last July with 4980 miles on the clock, now she reads 7100 or so. The bike is super clean and appears to be very well cared for.

The fuel pump primes, then the immobilizer light flashes twice and stays lit - that indicates immobilizer antenna or key error. I tried both my black keys and my red key with no luck.

I've pulled off all the body work and checked every connector I can reach. I've found no corrosion and no water inside any connections, in fact they're all in excellent condition. Start button switch is clean and perfect inside.

I'm no electrical wizard but I can use a multimeter to check resistance and testing the immobilizer antenna I get 17 ohms which I believe shows it is good.

Battery is new from last summer and tests strong.

I can power the starter directly from the battery and it cranks over fine but won't start.

I've swapped relays, checked fuses, checked grounds - yes the ecu ground is hooked up and clean.

I'm fairly certain my issue lies with the immobilizer control unit so I guess my options are to replace it or bypass it, but I wanted to see if anyone has run into this situation and had any insight. I've been reading about others with similar issues but either their engine cranks but won't fire, or the thread dies out with no real solution posted.

Also, what cables/software is currently recommended to bypass the immobilizer?

Thanks in advance!
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