HC96X Aux6(Vtec) no voltage

[Lokman]

I have an ECU HC96X,

The Aux6 has no voltage coming out even on test mode,

set to low and high side drive

Anyone have idea how to fix

map 20240707 1632 Good.pclx

[Vaughan]

Low side drive means that it will either ground the output or leave it floating, high side drive means it will either provide battery voltage to the output or leave it floating, not all plugin ECUs have the high side driver chip for Aux5-8.

Aux 5&6 on your particular plugin have FETs on the bottom board to change from Low side to high side and so should be setup as Low Side Driver and Active Low. Wen you have Aux 6 setup to Low Side Driver Type and active low can you set Aux 6 Test to ON and then check the voltage between pin A8 (positive) and A9 (ground).

[Lokman]

On 7/8/2024 at 5:40 AM, Vaughan said:

Low side drive means that it will either ground the output or leave it floating, high side drive means it will either provide battery voltage to the output or leave it floating, not all plugin ECUs have the high side driver chip for Aux5-8.

Aux 5&6 on your particular plugin have FETs on the bottom board to change from Low side to high side and so should be setup as Low Side Driver and Active Low. Wen you have Aux 6 setup to Low Side Driver Type and active low can you set Aux 6 Test to ON and then check the voltage between pin A8 (positive) and A9 (ground).

Yes Vaughan, my ECU is plugin and should be support with 12v from AUX 1 to AUX6,

The problem happening on me is that the Aux3 for AC Clutch and Aux6 for VTEC has 0volt even on test mode 'on', i have checked with testerpin on ecu plug.

Which cause my VTEC is not engauging although the ecu show AUX6 is active, which should be sending 12v for soleniod.

The Active state is low and higher side load for the VTEC.

Is it the map setup problem?

Thanks

[ae82ted]

You seem to got it in reverse...... Switched 12V should always go to the VTEC solenoid, and ECU Trigger AUX6 to ground for engaging the VTEC Solenoid. 

[Vaughan]

On 7/13/2024 at 11:43 PM, Lokman said:

The Active state is low and higher side load for the VTEC.

 

It needs to be Low Side Driver Type.

On 7/14/2024 at 4:34 AM, ae82ted said:

You seem to got it in reverse...... Switched 12V should always go to the VTEC solenoid, and ECU Trigger AUX6 to ground for engaging the VTEC Solenoid. 

Not uncommon for VTEC Solenoids to be grounded through the head and so need to be high side switched which is the case in this situation. The plugin for this car however has hardware on it to flip the output of the low side drive to high side.

[Harold C]

Hi,

Here is my setup for vtec, as Vaughan said, it needs to be low side :

Personally, I had to use a relay to have enough power to engage the solenoid. It might the same for you.