New Member RX-7 Technical Post your first technical questions here, in an easy flame free environment, before jumping into the main technical sections.

FC3S Main Fuse blows when battery is connected

Thread Tools
 
Search this Thread
 
Old 05-20-23, 10:24 PM
  #1  
Junior Member
Thread Starter
 
indebt4fc's Avatar
 
Join Date: May 2023
Location: Canada
Posts: 10
Received 0 Likes on 0 Posts
FC3S Main Fuse blows when battery is connected

I rebuilt my engine and reinstalled it and when i connected the battery, my main fuse instantly blows making me think there is a short, I looked at the wiring diagram and still can't figure out what might be the cause, I'm currently redoing the grounds.
Old 05-21-23, 12:30 AM
  #2  
Hey...Cut it out!

iTrader: (4)
 
Akagis_white_comet's Avatar
 
Join Date: Dec 2007
Location: St Louis, MO
Posts: 2,067
Received 295 Likes on 191 Posts
Originally Posted by indebt4fc
I rebuilt my engine and reinstalled it and when i connected the battery, my main fuse instantly blows making me think there is a short, I looked at the wiring diagram and still can't figure out what might be the cause, I'm currently redoing the grounds.
This belongs in the New Member RX-7 Technical Section, and will be moved accordingly. Please keep that in mind. As for the Main Fuse blowing on powerup, this is a dead short, plain and simple. It would be on the side opposite of the battery, do you see any damaged wiring? Since the Main Fuse also feeds several other fuses, it would NOT be on the circuits those other fuses operate as a lower-rated fuse would blow before a larger one will. It will be a game of "one of these things is not like the others", and the alternator can be ruled out since it is on the Battery side of the fuse box.

Realistically, the source of this problem will be under the hood, and probably close to the fuse box. I'd suggest taking a look at the Power Distribution of the wiring diagrams. Look for what the Main Fuse feeds, but Is NOT tied into another fuse.
Old 05-21-23, 10:07 AM
  #3  
Moderator

iTrader: (2)
 
rxtasy3's Avatar
 
Join Date: Jun 2002
Location: Spartanburg, SC
Posts: 9,315
Likes: 0
Received 256 Likes on 237 Posts
thread moved. please post in the correct sections.
Old 05-21-23, 03:02 PM
  #4  
Junior Member
Thread Starter
 
indebt4fc's Avatar
 
Join Date: May 2023
Location: Canada
Posts: 10
Received 0 Likes on 0 Posts
I did as you said and I believe I found the issue, my ecu ground was on the battery terminal of the alternator
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jet Alone
1st Gen General Discussion
2
12-14-22 05:44 AM
mori9863
2nd Generation Specific (1986-1992)
17
03-22-08 11:19 PM
itschrisfoo
2nd Generation Specific (1986-1992)
6
06-13-07 12:32 PM
thebrownone
2nd Generation Specific (1986-1992)
3
03-01-07 11:46 AM
blu_gxl
2nd Generation Specific (1986-1992)
8
09-20-02 04:11 PM



Quick Reply: FC3S Main Fuse blows when battery is connected



All times are GMT -5. The time now is 09:15 AM.