Electrical Question #15 Need Help Please, I'm totally stumped this time |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Electrical Question #15 Need Help Please, I'm totally stumped this time |
76-914 |
Apr 6 2014, 06:33 PM
Post
#21
|
Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,611 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
I'm going to have several electrical questions. 1st, Is pin #8, on the 14 pin plug at the relay board, the only switched 12v+ source in the engine compartment? TIA, Kent
|
Tom |
Apr 7 2014, 11:37 AM
Post
#22
|
Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
Kent,
Don't know why as they don't draw that much. Is the Subie ECU controlling them? If so, that feature may already be in place inside the ECU because Subaru found it to be an issue, but I don't know for sure. If you found it to be a problem, it wouldn't be that hard to remedy. A 30 amp relay wired for the starter circuit to open the fan circuit. Basically the fan power to 30, ground to 85, fan energized to 87A (NC contact), and starter power from the key switch to 86. Whenever the starter circuit is energized, the relay opens and fans have no power. Stop starting, power to fans is back. I think this would mostly depend on how much current the fans draw if the engine is hot and both are running to cool it. Say you drive 15 miles to the store and are inside 5 min and come back out. Would the fans still be running? This would also be determined on the battery condition and CCA. A battery with 500CCA will give 30 seconds of cranking at a big amperage without falling below a certain percentage of battery voltage. So if the starter is drawing 120 amps and fans 30 amps, that should not be a problem unless the battery is on the way out. Tom EDIT: Cold cranking amperes (CCA) is the amount of current a battery can provide at 0 °F (−18 °C). The rating is defined as the current a lead-acid battery at that temperature can deliver for 30 seconds and maintain at least 1.2 volts per cell (7.2 volts for a 12-volt battery). It is a more demanding test than those at higher temperatures. This is the most widely used cranking measurement for comparison purposes. |
Lo-Fi Version | Time is now: 27th September 2024 - 01:12 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |