I’m not the first person to need accessory power in a Chevy truck – but it took a while to find a solution.
One possible solution is to just put a tap splice on the stereo ignition wire – but this is iffy. In this case, I’m not posting something I engineered – but rather, some details to go along with what someone else was wise enough to figure out.
This link has the basic instructions:
http://www.dieselplace.com/forum/71-information-place/19-do-yourself-useful-articles-product-reviews/351435-rap-how-nbs-keyed-accessory-power.html
but he calls out some specific connectors and such that may not be readily available at Autozone or O’Reiley’s
First thing’s first – as everyone points out… the RAP (Retained Accessory Power) power at the connector is only capable of about 300 mA – so DO NOT power accessories direct from this connector. USE A RELAY.
Now – I used the quick connect terminals from Autozone that are slightly smaller than 1/4″ – Autozone part number 85446 – i think they were 3/16″.
Put these on, crimp, then solder them. The trick is to put heat shrink over the metal part once you’re done.
These can then be pressed on to the terminals that diesail calls out in his post.
I used pin 2 for constant hot, and it worked quite well for me… (updates to come – possibly with photos)