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NO IGNITION LIGHTS WHEN TURN KEY BUT CAR STARTS

2K views 5 replies 5 participants last post by  Hemikiller 
#1 ·
Hi:: I have a 1971 Mach 1 mustang C351 manual. just bought this vehicle. when I turn ignition key I get no ignition lights on dash but car will start and run fine.
previous owner has put electronic ignition on distributor. don't no if it is relevant. can't find any loose wires any where . I'm running out of ideas.
If any one can help would be appreciated.
Thanks
AL
 
#2 ·
Look for a failed splice in the ignition switch "C" circuit, which is "hot" in the "on" position. Power not only goes to the ignition system, but a splice branches off to the fuse panel, the IVR (instrument voltage regulator) and warning lamps. There is also a "prove out" circuit on the ignition switch that supplies specific warning lamps such as the brake system lamp with a ground signal in "start" to test the bulb.
 
#3 ·
I'm don't quite follow what you mean by "Ignition lights". Woodchuck is right as usual, and the dual brake warning light should come on with the ignition switch in the start position. The following schematic is specifically for a 69 but I suspect yours works the same way. The bottom right section shows the dual brake circuit. The left side of the page shows all the interior lights. A word of caution; schematics are intended to show how it works, not how the wires are connected. It doesn't show wire colors either.
 
#4 ·
only light on that car is the brake warning light. maybe the bulb is out
 
#5 ·
#6 ·
If the 71 has idiot lights, then it should have TEMP, ALT, OIL & BRAKE lit up at prove-out.

If it has either of the two possible gauge packages, then the only light lit on prove-out is BRAKE.

It's pretty common for the twist connector to lose connection with the printed circuit on the back of the gauges. Sometimes just doing an R&R on the bulb & housing solves the issue.
 
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