2000 Navigator- Problem starting

[KC-TN]

2K Lincoln Navigator won't start. Battery and all
electrical appears is fine. Possibly related to
anti-theft, chip-in-key, problem? I unhooked the battery cable for about 15 min, used two sets of original keys to MANUALLY unlock door, got in and
it cranked. HOWEVER, as soon as I got home and turned
it off, tried to start it again, and no-go.. Same symptom. All lights, dashboard, work fine. HOWEVER,The RADIO and PHONE WILL NOT WORK. Someone told me that they
believe it's related to anti-theft system, and/or transponder key being recognized by chip somewhere else ?
Hope someone has some ideas before I tow it to the dealer?

[ekooke]

If your radio doesn't work when it does this but the lights do, something is blocking the current flow to/thru the ignition switch. Anti-theft circuit is most likely. Also, if your Nav has those cheap stamped battery terminal connectors, replace them with something aftermarket (just about anything but copies of the originals), since they WILL cause other starting/charging problems sooner or later: Been there, done that.

[KC-TN]

Thanks.. Someone on the fordtrucks forum suggested removing the NEG terminal on the battery, as opposed to the POS terminal.
This clears any theft codes in the PATS system. Going to go try this now...

Note taken on the terminal connectors.. look sorta chessy, but they are in-tact, no corrosion, etc.. Do you have any idea of the path of the anti-theft ckt.. There are numerous fuses and relays. Fuses I can visually check, but relays? I have no way of knowing good or bad. I have noticed each time I turn the ignition, one of the relays under the driver side "clicks"..?.

[ekooke]

Removing either terminal will clear things, but removing the negative is safer (less sparking).
I know what the path is on my Mark VIII (scary), but yours may be different. I have the FACTORY service manual and EVTM for mine; this is a MUST for people that want to do their own SUCCESSFUL repair work on their vehicles. You can order thru your F-L-M dealer, or go to www.helminc.com (http://www.helminc.com) and buy direct.
These also show up on eBay and can be cheaper that way, if a 'bidding war' doesn't start up.

[KC-TN]

Well...got the Navi started. The battery cables didn't do it. I took an insulated screwdriver, and "jumpered it" across what I believe to be the solenoid.?. (bolted to firewall up/on left side as you're facing the engine.?.It sparked and the engine fired right up. I had my wife try to start again, and it didn't..but I just tapped on the solenoid and it fires everytime..everytime I tap on it, that is..?.

Looks like an easy job to replace, and should be inexpensive.?.. Keys, remote key locks, and auto-theft systems appear to check out ok..to the best of my knowledge.

[ekooke]

Sounds like you found your problem. Easy to replace and doesn't cost much. Go for a genuine Motorcraft part, and disconnect the battery before replacing it, so you don't fry something that'd be more expensive to fix. Also, check for a recall on the part, since it may be covered by Ford (for free).