Ecu Update For Vibration At 40mph

[rvtravel]

Has anyone installed the ECU update for 400h to determine if the battery or engine should be engaged for power at 40 MPH? (FP number 89981-48030)

If so, did it fix the vibration problem at 40 MPH?

Was there any affect on the gas mileage?

Thanks for replies.

[bikeandsail]

Has anyone installed the ECU update for 400h to determine if the battery or engine should be engaged for power at 40 MPH? (FP number 89981-48030)

If so, did it fix the vibration problem at 40 MPH?

Was there any affect on the gas mileage?

Thanks for replies.

What is this issue? I have a slight steering wheel vibration athe peaks about 37mph and was not fixed by tire balance or wheel alignment. I don't see any service bulliens on this subject!

Ron

[rvtravel]

GOOD NEWS: After Engineering change was installet, There is no longer a vibration when holding at a steady speed between 35-45 mph.

BAD NEWS: Now when I reach the spead between 20 and 40 mph, let the power monitor go to zero, the engine keeps running and the electric motors are not running. Before on level road the electric motors would be the power source with the engine engaged if neeeded.

It is too early to tell what effect this is going to have on my fuel mileage. Prior to this change, I was averaging 27.2 mpg.

[jerryray]

GOOD NEWS: After Engineering change was installet, There is no longer a vibration when holding at a steady speed between 35-45 mph.

BAD NEWS: Now when I reach the spead between 20 and 40 mph, let the power monitor go to zero, the engine keeps running and the electric motors are not running. Before on level road the electric motors would be the power source with the engine engaged if neeeded.

It is too early to tell what effect this is going to have on my fuel mileage. Prior to this change, I was averaging 27.2 mpg.

Ouch, my dealer told me not to do it unless I had the problem and it annoyed me, because it cannot be undone.

Hope it works out.

[Troy Lexus]

RVTravel - Where did you have the ECU update done. I have the same issue, and am going round and round with Lexus Customer Assistance after the dealer didn't have a fix. They are telling me they have not heard of the problem, and that it is "normal". From this and other forums, it's clear that there is a problem, and it can be resolved either by replacing the computer or performing the ECU update. At this point, I'm really disappointed in the response from Lexus. I came from an Acura MDX, which was a great vehicle. I wanted to try Lexus and the hybrid technology, but this may be my first and last Lexus if they can't admit to and resolve this issue.

[rvtravel]

RVTravel - Where did you have the ECU update done. I have the same issue, and am going round and round with Lexus Customer Assistance after the dealer didn't have a fix. They are telling me they have not heard of the problem, and that it is "normal". From this and other forums, it's clear that there is a problem, and it can be resolved either by replacing the computer or performing the ECU update. At this point, I'm really disappointed in the response from Lexus. I came from an Acura MDX, which was a great vehicle. I wanted to try Lexus and the hybrid technology, but this may be my first and last Lexus if they can't admit to and resolve this issue.

I had the update done at Lexus in Knoxville, TN. There is no longer any vibration and the mileage is a little better in the city.