dawgfanjef

Some background, not sure it it's relevant or not.

Bought 4 yrs ago from Sister in law with full service records and well maintained. Had some body work done after I hit my mailbox (5mph). Since the day I picked it up from the shop, my VSC light is on and has stayed on and when the lights are on. Since then, I have a "light out indicator" which was correct. I had a dead bulb in a side lamp. The bulb is replaced and working, but the indicator still lights when the lights are on. I can live with both of those.

However, I am in Atlanta, so every yr, I do an emissions check yearly when the car is re-registered. Never been an issue before, but now...two places with machines of different manufacturer, cannot connect to the computer. Power is good to the port, but the connection fails. The second guy was able to connect with his code scanner, perform a full scan with no codes registered. rrgh.

Am I looking at a 2nd hand computer and an afternoon to install, or is there something simpler to check? I am no mechanic, but I have proper tools and some skills, so I can hopefully DIY that if I need to.

Lexuswiz

iTrader: (1)

My first would be to check the voltage of your electrical system/battery at idle and after it has sat for awhile. Idle should be around 13.8-14.5v and sitting should be a tad over 12v. The ECU and BECU can do funky things when the voltages are out of wack. Also check all your grounding points.

It also wouldn't hurt to disconnect the battery for a few hours to see if a power reset of the ECU would help.

DennisMik

check the 7.5 amp fuse labeled OBD in the fuses under the dash. This supplies 12 volts to pin 19 of the OBD connector. If the OBD reader does not find 12 volts on pin 16, most readers will not work.

dawgfanjef

Thanks for your ideas...all of these checked out ok. Disconnected battery for 5 hours or so...still no joy. I am 0/4 now.... Time to investigate new ECU.