Hondata

K series engine
AEM 5 bars map sensor
2 ECU tested
voltage at ECU input work with voltmeter

I installed a AEM 5 bar map sensor, I did it several time on customer cars. But this one I have a problem
Once scaling with any custom or Preset Map sensor the Value still don’t move according to vacuum
On stock map sensor scalar (5bar sensor still be used), when I change the vacuum or boost on the pump the value in the ECU change
Once program custom or Motec 5 bar, the value is now fix and won’t move.
-I test 2 ECU
-I always used my voltmeter as ECU input terminal A19 Everything work there
-The voltage on the input (voltmeter) change perfect according to the amount of vaccuum or boost I put with my vacuum/boost pump
-I erased several time the ECU, 1 min Key OFF
-Test new base cal, test the same on the other ECU. It show us 14.417V at atmospheric pressure in the infos

I attached a screen shot showing weird Voltage from MAP sensor when stock
I attached a calibration file and datalog showing -29"/psi, but the voltmeter measued 1.35VDC

Ignore the 'volts at standard atmospheric pressure' if you have a stock map selected.

How did you measure the MAP voltage? You should measure on the ECU pins. If you unplug the MAP do you get 5V? I suspect the MAP wire is shorted to ground.

One more thing is that if a MAP sensor is wired incorrectly it will damage the MAP sensor and you will have to replace it.

As I wrote, the MAP voltage is measured with Voltmeter at the ECU pins, I see the voltage 1.33V with Key ON, Engine Off

If the MAP is short, the voltage on the signal MAP ECU input should not work

here is a video I take on my last testing

https://www.youtube.com/watch?v=_MKM2n9 ... e=youtu.be

Does someone have an idea?

I would read the voltage off the ECU pins. Should be A18 to A19.

A18 is VSS I think you made a mistake

Key ON i have on the sensor wires (at ECU) with the sensor connected
A11 is SG1 (Logical Ground for MAP) 0.8VDC
A19 is MAP Signal 2.03 VDC
A20 5.8VDC (VCC 5V)

the Logical ground have 0.8VDC difference between ECU Ground and Logical ground, I make bench on a bench by only putting power du ECU power and ground and sill have the same 0.8VDC
the Sensor still have 5VDC Since 5.8 - 0.8V = 5V

On the bench by poweing by A2-A4 the map sensor still wont read correctly (see attached files)

File

here is the test on the bench, with another computer, new beta software

Stock map sensor work, but as soon as the Map sensor scaling is change is stop to work

https://www.youtube.com/watch?v=9L-qCt1q_Fg

It will not read the sensor properly until the engine is running. You cannot test this on the bench as you are trying to do.