96 Tahoe, Need 12 volts when cranking

[khenry]

Hi, In 2019 I put a 383 motor in a 96 Tahoe 4X4. It has the MSD Atomic EFI fuel injection, MSD 6AL ignition controller, MSD Blaster 2 coil, MSD Atomic TPS controller, and the trans is controlled by a US Shift Quick 4 controller. To start the truck I turn the key to the on position, then I have a push button to crank it over to start.The transfer case and front Differential electronics has been removed and is now manual. The ECU has been removed, and replaced with the Atomic EFI ECU. My problem is, now for some unknown reason I am not getting spark. the 6AL controller needs 12 volts in the run position and during cranking to be activated. The wire I have it hooked up to drops below 8 volts during cranking. I need help finding a wire that puts out 12 volts on run and during cranking and doesn't drop in voltage.
Also, I did a self diagnostics on the 6AL controller and when the ignition is turned to the on position I am not getting the 5 LED flashed from the controller, and when cranking I get 6 flashes from LED.
Thank you very much for you help.

 

[Doubeleive]

Hi, In 2019 I put a 383 motor in a 96 Tahoe 4X4. It has the MSD Atomic EFI fuel injection, MSD 6AL ignition controller, MSD Blaster 2 coil, MSD Atomic TPS controller, and the trans is controlled by a US Shift Quick 4 controller. To start the truck I turn the key to the on position, then I have a push button to crank it over to start.The transfer case and front Differential electronics has been removed and is now manual. The ECU has been removed, and replaced with the Atomic EFI ECU. My problem is, now for some unknown reason I am not getting spark. the 6AL controller needs 12 volts in the run position and during cranking to be activated. The wire I have it hooked up to drops below 8 volts during cranking. I need help finding a wire that puts out 12 volts on run and during cranking and doesn't drop in voltage.
Also, I did a self diagnostics on the 6AL controller and when the ignition is turned to the on position I am not getting the 5 LED flashed from the controller, and when cranking I get 6 flashes from LED.
Thank you very much for you help.

I am not personally "real" familiar with the aftermarket ignition that has been added but you could connect a relay directly the to the battery and controller and use your crank signal as the trigger, that would ensure 12v is going right to it. check that your grounds are clean and good also.

 

[khenry]

I double checked and grounds are good. The relay sounds like a good idea, but don't know how to wire it. Would the relay go between the control box switch on wire and the on position of the key? I think I can figure it out. Thank you very much Doubeleive for your help.

 

[drakon543]

run your ignition trigger wire through a relay and have the relay run the box instead. have too much stuff running through that circuit to maintain 12v

 

[Doubeleive]

I double checked and grounds are good. The relay sounds like a good idea, but don't know how to wire it. Would the relay go between the control box switch on wire and the on position of the key? I think I can figure it out. Thank you very much Doubeleive for your help.

just look up fog light relay wiring diagram on google there are tons of examples/diagrams, it's pretty easy to do. It should fit right in with your existing mods.
I wire HID's this way because they draw a lot of juice and they tend to work crappy if not wired up with relays. sometimes factory wiring is not best suited for upgrades.

 

[khenry]

Thank you again for your help, I appreciate it.

 

[khenry]

I went ahead and put a MSD HEI distributor in and with EFI not controlling timing and its running 100 % better.
Thanks again.