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rpmerf · 02-04-2019, 11:00 AM

I like to use a test light - easier than trying to read a multimeter when you are in a tight spot. Start at the battery and move out.

+ to - on the battery
+ on battery to frame, block, body to verify good ground.
Start working your way down the line. Use the frame or body for ground.
Make your way to the fuse block.

Since you are having problems after the key the main things you want to check are:
Is power getting IN to the ignition switch, and
Is power getting OUT of the ignition switch to the proper circuits.

If you are not getting power TO the switch, you need to follow everything from the battery to the ignition switch. If it is going in, but not coming out, you either have a bad connection or a bad switch.

EDIT:
Schematics: http://forum.73-87chevytrucks.com/sm...?topic=11766.0

Looks like:
RED is power into the ign switch
PINK and ORANGE are RUN
PURPLE or YELLOW is START (depending on auto / manual)
BROWN is ACC

02-04-2019, 11:00 AM	#17
rpmerf Registered User Join Date: Feb 2011 Location: Parkville, MD Posts: 1,024	Re: Electrical Gurus - 87' no keyed power I like to use a test light - easier than trying to read a multimeter when you are in a tight spot. Start at the battery and move out. + to - on the battery + on battery to frame, block, body to verify good ground. Start working your way down the line. Use the frame or body for ground. Make your way to the fuse block. Since you are having problems after the key the main things you want to check are: Is power getting IN to the ignition switch, and Is power getting OUT of the ignition switch to the proper circuits. If you are not getting power TO the switch, you need to follow everything from the battery to the ignition switch. If it is going in, but not coming out, you either have a bad connection or a bad switch. EDIT: Schematics: http://forum.73-87chevytrucks.com/sm...?topic=11766.0 Looks like: RED is power into the ign switch PINK and ORANGE are RUN PURPLE or YELLOW is START (depending on auto / manual) BROWN is ACC __________________ 1970 C20 Custom Camper - 350, TH350 1997 GMC Suburban 1994 Acura Integra GSR 1987 Dodge Daytona Shelby Z Last edited by rpmerf; 02-04-2019 at 11:09 AM.