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My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.
From what you have described here this sounds like a fault with the EIS (electronic ignition switch) itself or an issue with the battery being weak or the battery connections being corroded or loose.Check for any battery connection or battery issues.If a fault is found it will need corrected to resolve this here.If this is checked and all found to be o.k. I suspect the EIS is acting up/failing needing replaced.This will have to be tested further to be sure.
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From here this sounds like a fault with the EIS itself with it needing replaced.I have seen this fail several times before in the past and had to replace it.I would have this tested to be sure this is the cause here before replacing it.Testing usually involves test equipment like a multi meter and either a dealers SDS machine or compatible scan tool for your model to be sure this is the cause here.I suspect it will be.
Did the key even rotate in the ignition with the used replacement EIS installed?