jaswood

In truth you could probably get by with a small AAA battery pak(9) and a capacitor or 2. Once the HV battery SOC is at a decent level and/or the ICE is running, the 12 volt battery isn't really required, a simple 12 volt POWER zener diode and a few capacitors would suffice.

Your question should really be "how little/small..?" The 12 volt battery charge level is maintained via a DC-to-DC voltage down converter from the HV battery. Keep the 12 volt battery capacity low enough that it can be easily (re)charged. Battery internal resistance MATTERS.

The knock sensor detection is below the level of human hearing and will generally be corrected for, enrich the mixture, before you would hear it even so. "Read" the message, don't "kill" the messenger (the knock sensor).

Crappy mileage and misfires would generally mean low fuel pressure....fuel filter or pump, or maybe clogged injectors. Tell the (St,d) to read the message, not kill the messenger (the knock sensor).

Back when the '01 premature failure reports started pouring into Lexus the initial reaction was to change the ATF change schedule from infinity, life of the vehicle, to 15,000 miles. AS time went on and more was learned about the failure cause(s) that was revised to a check the ATF condition at each oil change and only address the issue if warranted by the ATF condition. The ATF should be light pink/reddish and be transparent.. At ~40,000 miles my '01's ATF was definitely burned and dirty, and then again at about 90,000 miles. Based on what I read on the internet I have expected a transaxle failure before now, maybe 120,000 miles...?

The fog and turn signal lights are off also....as are the high beams in low beam mode.....does THAT look weird..?

I think the issue might be more like 150, or more, highway miles driven. 20 miles is not typically enough to result in even one HV discharge/charge cycle.

The relay is energized ONLY in factory DRL mode so DRL LED extinguishes with headlight activation.

Due to the relatively high resistance of the relay coil the high beam bulbs are not illuminated in DRL mode, only high beam mode.

The high beam socket has a standard high beam bulb and operates as so.

I might provided a major repair is really needed. Most probable candidate at the moment is our '01 "awd" RX300 pushing 100K and I expected transaxle failure before now.

The headlights are NOT on. In real life that BRIGHT white light is a relatively tiny narrowly focussed beam. Camera (lens?) made it "splatter".

When you switched in the "other" sensor was the battery disconnected long enough that the ECU had to "relearn" all of the sensor operating parameters, ALL sensors. And it will take up to 200 miles of "mixed" driving to relearn. At idle or simple cruise it is the upstream oxygen sensors that are used to control, SOLELY used, the A/F mixture. Only under "power" production mode is the A/F mixture control switched over to the MAF/IAT module.

On my '95 LS there is a servomotor that control the blend door and via a cable through the firewall a coolant flow valve to the heater core. This valve will stick due to coolant residue and then not only will the valve not always open the position of the blend door might affected. You can also get better heating response if you TURN OFF the A/C. Low MPG is more likely than otherwise the result of a blocked exhaust flow in the catalytic converter. Over time and use the honeycomb structure of the catalyst crumbles and will oftentimes, even interittently, block the exhaust ourflow from the catalyst. Generally no CEL to indicate this fault.

Wiring issues...definitely, but far beyond that. If you really want a "captive" GPS/Nav system a car trade would be more appropriate.

Night time picture and after many tries, camera settings, I just couldn't replicate what I was actually seeing. Brightness of the DRL LED is much more pronounced in the picture that in real life.

No sure how long these have been installed, probably bac in about 2008 when I discovered the problem. But with only a 10% dutycycle they most certainly will NEVER fail due to overheating.

DRL relay is at the bottom left, red and blue spade lugs... LED driver module is the white box in the upper right. The relay only energizes in the RX300's DRL mode. When energized the relay supplies power to all street/parking/marker/tail lights and the LED driver module. The LEDs are 3W with a 140 degree pattern and are mounted rearward facing the reflector and at the proper reflector focal point. The LEDs are "overdriven" by 50%, 450 milliamps, but the voltage dutycycle is only 10% at 10Khz. Human eyes cannot discern flickering above >40Hz.

My apologies. Obviously I misread the MY of the donor vehicle.

A low coolant will do that also. Another thing might be a "vapor lock", air bubble, in the hoses to/from the heater core, often resulting from low coolant and persisting even after coolant is filled.

Paragraph beginning with Dave Hermance down the page. http://www.familycar.com/RoadTests/LexusRX400h/ ....

.... Just wondering, what country are you from? We seem to have a communication problem. Speaking of being condescending....

EDIT: Caution This retrofit involved a '99 Porsche 911/996 wherein the headlight auto-leveling motor was used to move the entire internal projector/reflector assembly up or down into the proper position for whichever mode was selected. With the "apperture" type projector installed the assembly needed to always remian in the high beam position and the apperture movement provided the low beam shading cutoff. I can well attest to the fact that unpowered auto leveling headlights will need to be manually re-adjusted from time to time. My guess is that due to the vibration of every day use the headlamps, over time, moved positionally. The reason I know is that I installed a set of HID projector beam headlight retrofit assemblies that used a solenoid actuated shading apperture to switch between high and low beam. I then didn't need the auto-leveling motor to move upward in high beam mode, OEM method to switch modes. So I disconnected the motor power. After a few months of having to readjust the beam position to often I revised the control circuit with a diode and resistor so that the head light assemby did not move between high and low beam modes.

I found the DRL voltage/current limiting power resistor on the underside of the battery platform and wired a 12 volt relay in series with it. The relay coil has a high enough resistance that virtually no current flows through the high beam, DRL, bulbs in DRL mode. Then I used the N.O. contacts of the relay to provide switched power to the 2 3W LEDs I installed in those outside corner lights inside the headlamp housing/assembly. The 3W LEDs only drop about 3 volts at full illumination so each has a power resistor in series to drop the additional ~9 volts. The new LEDs are centric mounted within a new reflector surround so the LED beam is aimed for distance visibility as are the high beam bulbs used as DRLs.

Your concern is misplaced, traction control has nothing to with emissions regulations/issues.