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Discussion Starter · #1 ·
Morning,
I have a P325 and P330 fault. I disassembled my engine and exposed my two knock sensors.
Here are the electrical readings:
EB1 TO ECM
Pin 1 to GND = 3.2K ohm Pin1 to Pin2 = 6.1 K ohm Pin 2 to Pin 3 = 3.05 K ohm
Pin 2 to GND = 3.2 K ohm Pin 1 to Pin 3 = 3.06 K ohm Pin 2 to Pin 4 = 3.05 K ohm
Pin 3 to GND = 146 ohm
Pin 4 to GND = 146 ohm

FRONT KNOCK SENSOR (2) REAR KNOCK SENSOR (1)
2.8 mV STATIC - NO ENGINE RUN 2.7mV STATIC - NO ENGINE RUN
tapped on block - no change tapped on block - varied up to +/- 4mV

HARNESS TEST EB1 TO SENSORS EB1 TO ECM
Pin 1 = 0.4 ohms Pin 1 = 0 ohm
Pin 2 = 0.3 ohm Pin 2 = 0 ohm
Pin 3 = 0.1 ohm Pin 3 = 0 ohm
Pin 4 = 0.1 ohm Pin 4 = 0 ohm

I suspect faulty knock sensor #2
Received new knock sensor #89615-12090 - Bench tested and results are as follows:
Resistance - Pin to GND = "OPEN" mV bench test (tapping) = 0 mV

I think this knock sensor is defective. My questions is --do you guys agree? am I testing this as I should? I do not have a scope.

I would appreciate any feedback you guys can give me. I would hate to put all this back together again, do the drive cycle and still have the codes.
Thanks
Mike
 

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Discussion Starter · #2 ·
Update to above...
I purchased another knock sensor. This time from Autozone. Same result as Toyotanation. "open" resistance and 0 mV.
I went to another Autozone that had a knock sensor in stock and they allowed me to bench test . Same thing. Then I went to NAPA Auto and tested yet another one (different Manufacturer) -Same Results. Originally, I thought the existing sensor that reacted to the tap test was good, but now? All four new sensors tested the same.
?? I also read on someone's post that a resonance sensor will only output at a particular frequency. Could it be that there are two different versions of a Toyota knock sensor? It really seems unlikely to me that FOUR sensors would be defective. I don't know how to proceed. Do I keep looking for a sensor that reacts to the tap test? Do I install two of the new sensors?
I went to Toyota and asked a service mechanic, but he was unsure about the expected electrical characteristics.
OMG!
 

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Does your meter have auto-ranging?

Are you using the meter’s AC voltage setting?

See this thread, where I put my Camry’s functioning knock sensor on an oscilloscope. The waveform is about 0.4 volts peak-to-peak.
 

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Discussion Starter · #4 ·
Does your meter have auto-ranging?

Are you using the meter’s AC voltage setting?

See this thread, where I put my Camry’s functioning knock sensor on an oscilloscope. The waveform is about 0.4 volts peak-to-peak.
Yes and Yes... I am in the process of re-assembling the engine. I installed the two new sensors.
 
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