Green light would not turn off when key is on. Car crank but would not start. Hook up Autel scanner. It would not connect to the engine function only body function like door lock power window ext. ecm has been check out and fixed by local company supposely
. It’s a 2003 es300. Any help is appreciated before take it to the shop.

 

Also pulled all the fuses inside and engine compartment all checked out good.

 

Which green light?

 

immobilizer System

 

Turn key to ON look for the check engine light. Report back if you see or not.

 

Check engine not on when key on position. It’s not communicate with the ecm

 

My guess would be bad key fob. Only has one key. All the windows locks work perfectly with the key fob. Try to narrow down the problem. Don’t want throw money into it and hope the best. Can shop check the function of the fob?

 

FOB has nothing to do with your problem, the engine computer is not getting power assuming no one removed the CEL bulb. About the only time I've seen the ECU not get power is when people hook up jumper cables backward and blow a bunch of fuses.

 

Next step is to check the pins at the scanner plug to see what the voltage are. And go from there.

 

I pulled all the sensors one at a time. Still the same. No check light on dash. Next check ecm getting power or not. Which pin and the color of wire should I check? Thx for any info.

 

Check grounds as shown here
https://www.japan-parts.eu/lexus/us/...wiring-clamp/6

 

Thx for the diagram checked the grounding points all measure 0 ohm. Still need the color of wire power the ecm. See if I getting power to it

 

Available here
https://techinfo.toyota.com/

 

Thx I bought a page show the wire diagram to the ecm from eBay for couple bucks.

 

+B and +B1 got 0 volt. So what’s next?