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1980 Scottsdale wiring problem

  
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1980 Scottsdale wiring problem

 
trm420 trm420
New User | Posts: 2 | Joined: 05/12
Posted: 05/29/12
07:38 AM

I have a 1980 Scottsdale Diesel, that I converted to gas with an Oldsmobile Rocket 350.

Truck is running great, but I am having a minor electrical problem.  I can't get the parking lights to work in the front of the truck.  The turn signals blink, but slowly and the side markers blink with the t/s but no parking lights.

Any help would be greatly appreciated.

Thanks  

waynep71222 waynep71222
User | Posts: 221 | Joined: 05/12
Posted: 05/29/12
11:17 AM

the brown wire is the parking lights...

light blue and dark blue are the turn signals to the front..

check the ground connections at the turn signal sockets...

don't bother looking for ground connections for the side marker bulbs.. you won't find any.. you will find a brown wire and the light or dark blue wire for that side..   this was a subject of a thread just yesterday...

this is one of the images from that thread that will probably help you.. its for like a 77/78 camaro the wiring colors for the headlights and the turn signals should be the same..

you will want to check the battery ground connections...

there should be a thick cable from the negative terminal to the engine block

there should be a medium thick cable from the negative cable to the core support or inner fender..

there should be a braided ground strap from the back of the motor to the firewall..

there may be ground straps from the body to the frame..

77Camgnd  

waynep71222 waynep71222
User | Posts: 221 | Joined: 05/12
Posted: 05/29/12
11:32 AM

looking at the diagram.. your ground connections for the headlights and the turn signal lights will be individual wires...

i have a 2 minute test if you have a digital volt meter...

set digital volt meter to 20 volts DC scale..

start the engine.. turn on the headlights..

1.  battery negative to the battery positive post.....  14.1 to 14.8 volts is expected.

2.  battery negative post to the engine block..   0.04 volts is expected.

3.  battery negative post to the body... 0.02 volts is expected..

4. engine block to the body.. 0.02 volts...

if you get 0.00 something is wrong.. change the meter setting to 2 volts DC and retest the last 3..  

an additional test.. frame or bumper to the battery negative..  still with the engine running and the head lights on.. i expect a 0.02 or 0.00 reading..   if you get more than 0.02.. add an additional ground wire..  thats 2/100th of a volt..

what you are measuring is voltage drop across a circuit..   this is a test i use all the time to find electrical issues...  one 98 c2500 had 8.5 volts on test 4.. between the engine and the body.. man did it run different after i fixed the filthy ground connection..

the electrons flow from negative to positive..  and electrons are creative.. will come from almost anywhere they can.. .
this is from an 87 c2500
87Chevysuburbanv8batterycables

1987Chevysuburbansixbatterycables

if you look carefully.. you will see the ground cables...