Posted January 21, 201411 yr comment_440008 There are two blue wires coming out of the harness behind the heater control panel. Both have in-line glass fuses. Both are not hot and not attached to anything. What are these for? Link to comment https://www.classiczcars.com/forums/topic/48382-240z-blue-wires-behind-heater-control-panel-1970-240z/ Share on other sites More sharing options...
January 21, 201411 yr comment_440009 I believe if you trace them back, one will lead to the fan switch and is a power lead provision for the air conditioner. The other may be a provision for an electric fuel pump.Are you a member of the Sun Central Z Club? If not, check out their facebook page. Link to comment https://www.classiczcars.com/forums/topic/48382-240z-blue-wires-behind-heater-control-panel-1970-240z/#findComment-440009 Share on other sites More sharing options...
January 21, 201411 yr Author comment_440010 The 1970 240Z had neither air conditioning nor an electric fuel pump. And there is no way to "trace back" wires through the harness. Both wires are cold with ignition on or off also. Link to comment https://www.classiczcars.com/forums/topic/48382-240z-blue-wires-behind-heater-control-panel-1970-240z/#findComment-440010 Share on other sites More sharing options...
January 21, 201411 yr comment_440012 The 70 and 71 240Zs were not equipped with AC or fuel pumps - or courtesy lights in the foot wells - or fog lamps, but they were included in the wire harness. You should consult the FSM and supplemental FSM for these years. Link to comment https://www.classiczcars.com/forums/topic/48382-240z-blue-wires-behind-heater-control-panel-1970-240z/#findComment-440012 Share on other sites More sharing options...
January 21, 201411 yr comment_440021 I will check later but one should be the factory radio power supply and the other for power supply to the heat blower. I know that is what I found when working on my 72 but the 70-71 could be different. Link to comment https://www.classiczcars.com/forums/topic/48382-240z-blue-wires-behind-heater-control-panel-1970-240z/#findComment-440021 Share on other sites More sharing options...
January 21, 201411 yr comment_440026 This may, or may not, be related to those blue wires, but thought I would add it to the conversation. The dealer added FrigiKing air conditioningincorporated a micro-switch that may have utilized one of these wires. The mirco-switch was mounted at the intake duct actuator located behindthe blower motor in the passenger side footwell area behind the dash. When the top slide lever on the heater control panel was moved from thecenter "vent" position to the left "off" position, the intake duct door moved to close off fresh air intake and open to allow the air from the evaporatorto pass through the blower assembly for cabin distribution. Also, with the movement of this vent lever to the off position, a circuit was completed via this micro-switch throught the dealer added A/C ON-OFF/ RHEOSTAT switch to allow electrical actuation of the A/C compressor. This on-off switchwas mounted to the bottom of the dash below the hazzard switch. The micro-switch assembly on my car is incorporated in a red plastic housingmounted next to the cable actuator for the intake duct behind the blower motor.I mention this for informational purposes only to help expand this discussion. This is just my personal understanding of this switches function, as I do not havethe original installation instructions provided for dealer installation. Dan Edited January 21, 201411 yr by AZ-240z Link to comment https://www.classiczcars.com/forums/topic/48382-240z-blue-wires-behind-heater-control-panel-1970-240z/#findComment-440026 Share on other sites More sharing options...
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