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Hello,

So I have a project with M800 and PDM15, and I have read the M800 pinout for sensor power supply, and it looks like there only have 5v and 8v supply for ref/sync sensor. My question is how about if I have a ref/sync sensor that need a 12v supply? Should I take it from PDM output direct? Please advise. Thank you in advance.

Yohan P.

HI Yohan,

Are you sure that the sensor uses 12V+? I have not seen a automotive sensor that uses this level of input voltage before, mainly because in a 12V electrical system, it isn't guaranteed that you will always have 12V+ available to provide a steady voltage input, thus a filtered 5V+ (most common) or 8V+ input voltage is used.

I would confirm that the sensor does actually need 12V+ fed to it first, so that you do not damage it, and if it does need to have 12V+, use the same supply as the ECU uses so that if the voltage dips on the ECU, then the sensor will have the same dip and (hopefully) not skew the reading from the sensor to much.

SDean wrote:HI Yohan,

Are you sure that the sensor uses 12V+? I have not seen a automotive sensor that uses this level of input voltage before, mainly because in a 12V electrical system, it isn't guaranteed that you will always have 12V+ available to provide a steady voltage input, thus a filtered 5V+ (most common) or 8V+ input voltage is used.

I would confirm that the sensor does actually need 12V+ fed to it first, so that you do not damage it, and if it does need to have 12V+, use the same supply as the ECU uses so that if the voltage dips on the ECU, then the sensor will have the same dip and (hopefully) not skew the reading from the sensor to much.

Hi Stephen,

It is the Honda K20A that I working on, can you help to advise which voltage supply for its ref/sync sensors?
Also attached the K20A ref/sync sensors drawing that I found on internet, I'm confused why it stated 12v on power supply?
Thanks a lot.

Yohan P.

They are Hal sensors. You can either use unregulated 12v or 8v.

gtihk wrote:They are Hal sensors. You can either use unregulated 12v or 8v.

Thanks a lot for the advise

When I did mine, Sensor power was not coming from ECU. It does not really matter.

gtihk wrote:When I did mine, Sensor power was not coming from ECU. It does not really matter.

So, to be clear, for sensor which need a 12v, I can get the power from 8v engine supply on M800 or also 12v unregulated supply? Is this also correct?

Hall sensors use 8 volts. ground pin is B16 or sensor 0 volts, signal wire you know already. use shielded cables or ecu will be easily confused with the signals and join the braids of the shield into the ground 0 volt. or you will see what ark design did to their r32 gtr

mfalah wrote:Hall sensors use 8 volts. ground pin is B16 or sensor 0 volts, signal wire you know already. use shielded cables or ecu will be easily confused with the signals and join the braids of the shield into the ground 0 volt. or you will see what ark design did to their r32 gtr

What happen to their R32?
and thanks a lot for the useful advise my friend.

It is the Honda K20A that I dealing with, would you be able to prompt which voltage supply for its ref/synchronize sensors?
Additionally connected the K20A ref/synchronize sensors drawing that I found on the web, I'm confounded why it expressed 12v on the power supply?

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