Friday, August 11, 2006
Tidying up loose ends
I've spent a couple hours today working on the Dart's wiring. Right now I have finished all the under-dash wiring, although I have the relays and fuses sitting on the transmission tunnel instead of behind the dashboard where they will go when I finish things. That should make things easier to troubleshoot. The low pressure fuel pump is wired up, but I will need to get a few connectors to hook up the high pressure one. Other than that, the wiring is done.
Finding a place to connect the wire for the main relay was a bit of a challenge, and I'm not 100% certain I picked the right spot. On newer cars, you hook the relay to a terminal on the ignition that gets power when the car is in the Run or Start position. Well, on the Dart, there is no position on the ignition switch that gets full power at both spots. The IGN terminal gets full power in the Run position, but if you connect anything to that when the engine is cranking, the power will go through the ballast resistor instead. And you don't want to splice the terminals together unless you are removing the ballast resistor. While I plan to do this later, right now I still need that thing in there.
In the end, I hooked it up to the IGN terminal anyway. The ballast resistor's resistance is much smaller than the relay coil's, so the relay should still function. If it turns out that the relay cuts out when cranking, I'll have to come up with some sort of OR gate to get power to the Megasquirt at either setting. Stay tuned to see how this works - I'm probably going to have it all together and start troubleshooting it by the middle of next week.
Finding a place to connect the wire for the main relay was a bit of a challenge, and I'm not 100% certain I picked the right spot. On newer cars, you hook the relay to a terminal on the ignition that gets power when the car is in the Run or Start position. Well, on the Dart, there is no position on the ignition switch that gets full power at both spots. The IGN terminal gets full power in the Run position, but if you connect anything to that when the engine is cranking, the power will go through the ballast resistor instead. And you don't want to splice the terminals together unless you are removing the ballast resistor. While I plan to do this later, right now I still need that thing in there.
In the end, I hooked it up to the IGN terminal anyway. The ballast resistor's resistance is much smaller than the relay coil's, so the relay should still function. If it turns out that the relay cuts out when cranking, I'll have to come up with some sort of OR gate to get power to the Megasquirt at either setting. Stay tuned to see how this works - I'm probably going to have it all together and start troubleshooting it by the middle of next week.
Labels: Dodge Dart
