'84 restoring -electrical grounds
Thread Starter
Racer
Joined: Sep 2010
Posts: 325
Likes: 7
From: Princeton Jct. New Jersey
'84 restoring -electrical grounds
I'm troubleshooting electrical problems on an '84 vette. The emergency flashers are working & LH turn signal works (slow flashing), RH turn sig. doesn't. The rest of the cluster is dark. I pulled the cluster out and checked grounds on the D1&3 connector pins. D1 reads 24 ohms (to chassis grn) and D3 reads about 4 ohms. Voltages at C16 & D16 read 11.6vdc. Section 8a in my GM service manual is missing (thanks GM). Where are these ground points? Any advice appreciated.
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Just so you know ... section 8A is in a separate manual "The electrical diagnosis service manual supplement."
Maybe Agent86 will chime in as he has pdf's of his 86 FSM available ... (sorry I can't help with the location of the grounds)
Maybe Agent86 will chime in as he has pdf's of his 86 FSM available ... (sorry I can't help with the location of the grounds)
Race Director
Joined: Aug 2007
Posts: 11,889
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From: Whitefish Falls Ontario
St. Jude Donor '08-'09
My 84 FSM has section 8A.. D1 goes to splice or crimp terminal S225 and then to G101 behind R/H side of instrument panel.. D3 goes to C100 to G110 which is LH rear of engine ( appears to be behind bellhousing bolt.) C16, D16 both go to 5 amp instrument cluster fuse.. What voltage do you get at your battery?? 
Thread Starter
Racer
Joined: Sep 2010
Posts: 325
Likes: 7
From: Princeton Jct. New Jersey
My 84 FSM has section 8A.. D1 goes to splice or crimp terminal S225 and then to G101 behind R/H side of instrument panel.. D3 goes to C100 to G110 which is LH rear of engine ( appears to be behind bellhousing bolt.) C16, D16 both go to 5 amp instrument cluster fuse.. What voltage do you get at your battery??
Thanks for the info, saved me a few hours of crawling under the car in the heat and humidity we have here in NJ. The batt. voltage reads about 11.9 vdc and is fairly weak and not holding a charge well (the car sat idle for about two years). According to the circuit diagram the 150 ground line has about 15 systems spliced to it and only half are working so the junction where the faulty systems are spliced might be the problem. Does the manual indicate the location of S225 ?
