The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 72 Sierra Grande wiring

Bigblock50 · 09-27-2020, 08:28 PM

Truck is automatic. I gave the neutral safety switch a careful check. Ignition switch “on” feeds power to the dark green wire for the backups. Ignition switch to “start” feeds power to one of the two purple wires.

I didn’t have time Today to test the HEI except to note that it has several wires attached. I’ll check them all tomorrow.

I did note while in the cab that when a load is put on, say headlights and heater blower, the ammeter does not respond. Not sure if it should or not. I checked the two shunt fuses, they’re fine.

09-27-2020, 08:28 PM	#13
Bigblock50 Registered User Join Date: Aug 2020 Location: Luray, VA Posts: 35	Re: 72 Sierra Grande wiring - still at it Truck is automatic. I gave the neutral safety switch a careful check. Ignition switch “on” feeds power to the dark green wire for the backups. Ignition switch to “start” feeds power to one of the two purple wires. I didn’t have time Today to test the HEI except to note that it has several wires attached. I’ll check them all tomorrow. I did note while in the cab that when a load is put on, say headlights and heater blower, the ammeter does not respond. Not sure if it should or not. I checked the two shunt fuses, they’re fine.