PuReChaos

The second set of photos I uploaded were for the 2000 ES, the first set I mistook the OP's request and uploaded 97 ES instead.

Here is a larger picture of the first one. Please let me know if I am not understanding you correctly.

tylojuky

Old thread resurrection:

Thanks PuReChaos - just in case someone else is searching like I was today, the pin-outs in your first set of pictures (post #9) are accurate for a 1994 Lexus ES 300 as well (same engine).
Funny how your "mistake" (posting the 1997 pin outs instead of the 2000) helped me out.
I did the hack on my son's 1994 ES 300 and it works like a charm. Much simpler than trying to do it under the hood - at least on the 1MZ-FE engine.

Thanks again.

mugencivic

Thanks tylojuky for bumping this thread. I have a 99 ES with CEL for a knock sensor ( i believe for only one of them *fingers crossed*). I never knew of this hack and I'm definitely going to try attempt it this weekend.

QUESTION: Does the crank sensor require the same voltage as the knock sensor?

tylojuky

No problem. I performed this hack similar to the pictures on past #64 here. The difference is the use of spade connectors instead of a wire tap. I put a SINGLE female spade connector on BOTH knock sensor wires entering the ECU plug. Then a single male spade connector on EACH of the 2 wires coming from the two knock sensors. I'm glad I did that because I guessed wrong the first time on which incoming wire was connected to the good knock sensor. That was easily corrected by simply unplugging that male spade and plugging in the other one.


I don't know what you mean by that question. I don't think either type sensor "requires" voltage (rather, they produce voltage). Maybe I'm getting hung up on that word and completely missing your question (?)
The knock sensor is, effectively, a microphone (a very specialized one). The crank sensor is, essentially, a magnet passing over a coil. At their most basic form, these are, technically, similar processes (moving a magnet over / through a coil). However, I doubt the voltage produced by the knock sensor is anywhere close to what can be produced by a crank sensor. This is a guess based on two observations:
(1) a crank has a lot more movement than a microphone and has an engine pushing so it can have a much larger/stronger magnet and there's plenty of room for a larger coil. Consequently, it would be easy to reliably produce significant voltage this way (compared to the tiny magnet and microscopic movement inside a piezo microphone).
(2) The knock sensors use shielded cables under the hood which makes me think the engineers were worried about electro-magnetic interference - implying the voltage carried is very low.
In any case, I doubt the signals look the same - even if you account for voltage differences.

All that is supposition based on education and experience in a completely different field. Someone who knows more specifics about the signals processed by these particular ECUs might read this and correct me.

Good luck.

mugencivic

thanks for explaining how both work. i guess my question was asked wrong and was leading to me bypassing that too. i know the importance of both sensors (knock and crank) but I'm use to messing with 90's Honda's where crank/knock sensors can be bypassed easily to avoid CEL's. from what i gathered, I don't think the ECU is as picky with the brand of crank sensor as it is with the knock sensor. Plus its easier to access than the knock sensor, so replacing it probably makes more sense.

tylojuky

Sorry - you ask, "What time is it?" and I tell you how to build a watch.

I can't help with the crank sensor. I know nothing about what kind signal the ECU is expecting nor what it does if it gets something different. Hopefully someone here can chime in.

mugencivic

No problem, I do appreciate you taking the time for responding to my questions. I realized that i need both knock sensors replaced, so this hack would do nothing for me

Gitano

If your looking for the wires to hack it's simple just find a how to do it post. There is nothing to it.

phiendasau

Hi Tylojuky,

My car is 2002 Lexus ES 300 and has the same problem P0330 as someone here. I searched and found your post are interesting. I am grateful if you can give me a ECU pin out or tell me how I can find it. Thanks for your time .

Arsenii

Hello,

Below is the ECU pinout that shows knock sensor pins.



Hope this helps and best of luck!

phiendasau

Hi Arsenii,

Thank you for your picture. Would you like to explain more to me about the picture ? What exactly is position of knock sensor on ECU pin out ? Excuse me for being really unfamiliar with it !!

Thanks for your time.

Arsenii

Sorry for the confusion, I made a more detailed post in the original thread. I didn't notice that you are the same person right away...

phiendasau

Thank you for your help Arsenii !! if possible please explain more about its location , I can't get its position . Thank you.