Gary, you didn't state a year, so hope i have the right diagram. Pin # 87 ign. relay, splits to feed 1) ckt#13P to ign adapter plug 2) ckt# 13H powering fuse #F4-C 3)ckt# 13-J powering heater control relay & ckt# 13-F to another ign adapter plug Hope this help... Login to read more.