Solved a Controversial Subject Yesterday
It has been discussed in different threads about when the I/C pump runs, I for one had started a thread called "Pulse Voltage" it was a term in the SRT 6 repair manual. I had finally called RENNtech and they said if the key is in the on position the I/C pump is running and a few other members had agreed that it was a true statement. Well yesterday I hooked up a meter to the pump and placed it where I could see it from the drivers seat. I turned the key to the on position, no voltage was displayed on the meter. Then I started the car - still no voltage, I slowly depressed the gas pedal all the way to max RPM while in park (around 3,800 RPM), still no voltage. I then shut the car off then started it back up and started revving the engine, starting out slow and kept revving more aggressively each time. The meter finally displayed 14.xx volts if you nailed the gas pedal fast and the voltage stayed on even when just ideling, I shut the car off and turned the key back to the on position - no voltage. So basiclly when certain conditions are met a relay latches for the pump control module and the pump stay's on as long as the car is running. I hooked up the meter to fuse #13 and done the same thing that I had done with it connected to the pump and got the same results, I believe this fuse is the last component in the I/C pump circuit. I went ahead & ran a couple wire's into the car to an LED I mounted by my HE temp gauge so that I would know when the pump came on. Wondering if the supercharger had anything to do with one of the conditions that needed to be met for the pump to come on, I pulled the connector off the S/C clutch and inserted a couple solid small gauge wire's then plugged the connector back in. I connected a LED to these wires to tell me when the S/C engauged and started this process over again, the pump came on, but the LED connected to the S/C never did. Being concerned that I did not have a good connection with the wire's stuck in the S/C connector, I had the wife come out to operate the gas pedal while I took the meter leads & periced them into the S/C clucth wire's. I had her slowly rev the engine and each time rev it more aggressively, the pump light finally did come on, but I never did get any voltage to the S/C clutch. I then had her rev the car slowly up to around 2,500 RPM - hold it for about 5 seconds then go ahead and nail it while I still had the leads stuck into the S/C clutch wire's. I got the crap scared out of me, I never did get any voltage on the meter, but at the top end of her nailing it hard the clutch did engauge for a split second and let out a BIG CHIRP. I don't know for sure, but I'm guessing some how my meter caused this split second of the S/C clutch engauging. I don't think the S/C has anything to do with the conditions that must be met for the I/C pump to come on. Now that know that the pump does not run with just the key on, I will be running a second circuit isolated from the OEM circuit to the I/C pump using a relay operated by my remote control HE fan circuit. This will let the coolant circulate and be cooled by the HE fans while the car is shut down, thus helping with the heat soak issues.