A couple of questions for the Thruster experts.
1. I am wiring the cooling fan accessory pack harness. Got it hooked up and just noticed the relays are NORMALLY CLOSED - ie, the fans want to run all the time unless they get a ground input.
So - does the PCM send a ground singal all the time, then break that ground to trigger the fans???? If not, I need to re-wire the relays. This is confusing because I've never seen a normally closed relay for electric fans - they are always normally open and then get the ground to close the relay either through a temp switch, or from the computer.
2. The a/c harness interrupt. Noting question #1 - the Vintage Air a/c sytem has a trinary switch that makes a ground signal to trigger a cooling fan relay once the clutch is activated. The Gen VII is suppose to be able to "interupt this" so that we can program at how much throttle the a/c will disengage. Now...because of #1 above - I'm confused as heck as to what to do with that ground signal and how that ties back in. I can't even simply feed this into the fan relays now because if I ground them...they shut the fan off. This is really two questions at once, as the Gen VII interupts the power feed to the clutch - not the ground coming from the trinary switch - but it is also suppose to allow for control of the fans through the main fan hook up based on a input signal from the a/c through the accessory harness.
3. THE BIG ONE - For some reason, after you turn the key on the first time - the computer doesn't want to drop power to the ignition AFTER you turn it back off. My local installer/tuner tells me he has now seen this several times and talks about making a jumper harness with a light in it...etc. to override the problem but he isn't sure how to fix it. In other words, you can't shut the car off with the key once it starts. Something is getting energized and staying engergized. I have the distributor and PCM feed coming off the car's coil feed that is hot when the key is on, and stays hot while starting so the fuel pump and computer/ignition will stay hot while cranking. However, when you turn the key off, the stock 76 trans am wiring shuts power off to this lead...but the system is now keeping the power energized. There are three switched power leads. One to the distributor, one to the 300 box, and one to the PCM. They should all require to keep power on during the crank cycle - and I'm not aware of any other way to fee that off the ignition switch than what I'm doing now. The other main power lead is direct to the battery as indicated along with a direct lead to battery ground.
What gives? I'm sure this is simple to correct.
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