The Number of Outputs setting
An automatic gearbox picks gears by switching a set of shift solenoids on and off in different combinations. The ECU needs to know how many of those solenoids it's driving. For many gearboxes it can work that out on its own from the Transmission Type and the Number of Gears you've already selected. A GM 4L60, for example, is known to use two gear select solenoids.
- Greyed out: the ECU already knows the answer for your transmission. Whatever value is shown is ignored, so there's nothing to change.
- Editable: the ECU can't infer it for this transmission type, and you must enter the correct number yourself. Leaving it wrong means the ECU won't command the right solenoid pattern, and the gearbox won't shift properly.
When you need to set it, check the page for your specific transmission in Haltech's supported transmissions information, which lists the solenoids it uses. If your gearbox isn't covered or you're unsure, ask us before you drive it.
What to set up next
With the outputs defined, move on to Outputs for Gear to set which solenoids are on in each gear, then the shift strategy in Auto Mode Shift Points. The overall feature is covered in Transmission Control.
