Hello, have had intermittent starting problems with my S-60 for a year or so. Will sometimes fire right up although usually I have to crank several times before it will fire. Then will occasionally run rough and stall and fire right back up and run fine. Local import shop diagnosed key was failing last year at which point I would pull key out of ignition, reinsert, and car would start after a couple attempts. Sometimes starter would engage sometimes not. Starter sounds fine when turning over. Other day it failed to start or energize starter. Took it to dealer because of key issue, they put new terminals on starter wiring and told me if it fails again, it's probably the starter. Screen showed immobilizer display for the first time the other day before it went to the dealer. I can change the starter easy enough, not sure if I might have something else going on as well. Hate changing parts by guessing! Appreciate any thoughts!!!

 

Have you tried resetting the immobilizer? Lock/unlock the car 5 times with the remote. Other than that try using another key if you have one.

 

Have only one key. Noticed this morning, the cables that come from the battery to the starter are are green at the end of the cables where the copper wire is exposed which seems to me might explain intermittent engaging of the starter. Seems to me I could have a couple of different issues going on here. #1) key possibly failing, #2) cables not able to carry enough current because of oxidation at end of cables to engage starter