Xoutpost.com - No start after extended dead battery

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Quote:

Originally Posted by Qsilver7 (Post 1129076)

Just an FYI to clarify this oft thought misconception...EWS does NOT require the battery in the remote key to work. If it did, then the valet and spare key wouldn't work because they don't contain a battery. EWS is self powered through induction. A 125 KHz RF signal is sent from the EWS control module to the Ring Antenna (around the ignition cylinder) which inductively powers the coil inside the key and allows the transponder soldered to the IC board inside the key to communicate back the ISN.

The battery in the remote key is only used to transmit the 315 MHz (or 433 MHz in Europe) radio frequency from the remote to the aerial in the rear right cargo window to initiate FZV/DWA (central locking/anti-theft alarm siren system).

:thumbup: Nice! I thought the battery contributed to the signal for the EWS to pick up. But as you mentioned, th valet doesnt have a batt. Forgot that part. Nice catch!

It was a long time ago when I fist posted this thread. I want to thank all for the posts and suggestions. Read several other threads as well and put the repairs on hold because life happens. Getting closer to my daughter needing the car so efforts have been directed again into getting it back up and running. Very long story short, it was a seized starter from our salty New England climate. Fixed it by accident when I was tapping the upper E12 socket onto the head of the bolt because it is partially stripped. Now I have 4 codes to sort out and get it back to purring like she used to.