1981 K15 Ignition Switch Wiring

[81SierraGrande]

Long story short, I have installed a new wiring harness in my truck, the ignition switch wiring I used was from the new wiring harness diagram (attached). Is this correct? It was a universal wiring harness with gm plugs, I am not sure if this is correct and can not find a good diagram to check. It also calls for the grounds to be during crank only and I have no idea what that means. I thought a ground was a ground? I have a short running through the system somewhere and this is one of the last things I know to check before I start pulling hair, cussing, etc.

[ray_mcavoy]

Some of the labels on that picture are wrong. On the black plug, the bottom cavity labeled "ground" and the upper cavity labeled "spare ignition" are reversed. Also looks like the "ignition" and "starter" labels on the white plug are reversed as well.

The "ground during crank only" means that the ignition switch has a set of contacts inside that momentarily connect those terminals to ground when the switch is in the "start" position. They're used to provide a "bulb check" of the "temperature" and "brake" warning lights on the dash. Grounding those circuits causes those lights to momentarily turn on while cranking the engine so the driver knows the bulbs are good (not burned out).

Thanks to hatzie, you can download wiring diagrams and service manuals here --> http://67-72chevytrucks.com/vboard/s...d.php?t=545416 Note: he doesn't have the 1981 wiring diagram available but the ignition switch wiring should be the same for 80 or 82.

[81SierraGrande]

I appreciate the feedback! I have been fighting this issue for the past few weeks and reached out on multiple forums and yours is one of the only constructive replys I have gotten. I have the wiring schematic for 81 I believe but the more I look at those things the more confused I get. Thanks again for the help