[painter203]

I've got an '07 corolla with 275k miles that has run like a top for years. Driving home yesterday cruising at 75mph it lost ignition and refused to start. Towed it home and now it says it can't communicate through obd-II port. All fuses check out and have swapped a few relays around. Voltage to battery is good. Any ideas? since I just sold my backup vehicle any help would be appreciated. Thanks. Everything in car still seems to have power and cranks.

 

[painter203]

The scan tool I am using is one that has previously worked on my car and tested on neighbors car..It still works. Thanks again.

 

[corollacoaster]

Check the fusible link on the battery.

 

[kevcules46]

Any bent or dirty pins on the cars port? I wonder if your ECM is toast and that was the "ignition off" situation and now it can't connect? Doesn't auto zone test for free? You would still have to get there I guess....
Good luck...

 

[75aces]

A bent pin is plausible. It’s happened to me before. Check your obd port on your scan tool for bent pins.

Try bumping your starter to see if it runs. Or you can apply power to the load side of the starter relay socket to listen for the starter energizing.

 

[GaryQ]

Check if ignition switch is working too by checking for voltage at any fuse that has power on acc, run and start and that it does in that switch mode. Sounds like a potentially dead ECU too but there are so many possible failure points it makes my head spin.

Check all harnesses and Grounds while at it. Even if none is the cause, it's a great opportunity to spot any potential future problem before it happens.

Best of luck.

 

[75aces]

Could also be a bent or twisted key.

 

[painter203]

I really thought (hoped) it would be a damaged key, but no.Tomorrow I will go through the harness.