Help- Vsc Light/check Engine Light, Harsh Shiftin

[bobs201]

my 06 GS300 started shifting kind of rough and when coming to a stop it would downshift from 3rd to 1st (skipping 2nd) causing a harsh thump as if the car just got rear ended. also the overdrive would kick in late when the accelerator is pressed hard. Took it to the Lexus stealearship' and they said it needed a $6500 transmission, saying the computer inside the tranny went bad. so my extended warranty company covered the cost and now the car is still shifting the same!! now they're saying it is the ECU, which is about another $2000! My warranty company is gonna flip when they hear this! They will probably not even cover it knowing they just wasted money in a part thats was not even the problem. Anyone with similar problems or any suggestions??

THanks

[boB_2006_GS300]

two things I would check are that your ECU fuse is good and that your battery is good and strong.

I inadvertenly pulled the fuse (while looking for another blown fuse) and replaced the ECU fuse in a spot that I though it came from, but returned it one spot off as there was an unused fuse space. The car had all of the same transmission symptons you are seeing. Seemed like the battery was not strong enough for the solenoids in the transmission. I thought I had a bad battery and replaced it. Still had trouble, thought the new battery was bad too. Don't know all for sure, but Lexus found the fuse that was in the wrong slot very fast and the car shifted perfectly since (about 4 years).

Bottom line, check that the ECU fuse is OK and has power.

[bobs201]

Thanks, where is the ECU fuse located? And what type of fuse is it?

[boB_2006_GS300]

Thanks, where is the ECU fuse located? And what type of fuse is it?

don't know. I had pinched a wire when I was installing an iPod adaptor that blew a fuse. there are fuse panels in the kick area on both sides of the car. while looking for the fuse I blew, I pulled them one at a time to look at them. turns out the ECU fuse was next to an empty fuse slot. I replaced it to that one by mistake. the dealer figured it out, but basically being in the wrong spot is the same as no power or a bad fuse. my car started, but ran poorly and shifting was like what you have.