Go Back   Infamous Nissan - Hardbody / Frontier Forums > Tech Area > Wiring and Electrical

Reply
 
Thread Tools Display Modes
Old 12-29-2016, 11:25 PM   #1
Lovemyhardbody
 
Lovemyhardbody's Avatar
 
Join Date: Nov 2016
Location: TX
Posts: 18
Vehicle: 90 Nissan d21
Thanks: 11
Thanked 0 Times in 0 Posts
Default Yellow wire coming from alternator

Hey guys back again.

Quick question- the alternator has 2 wires that plug into the top
One is thick and white- and it goes to the positive battery terminal and the top post on the alternator, right?

The yellow one goes where?

The reason I'm asking is because my yellow (with brown spots) is not attached to anything- it's cut about 6 inches from the plug.
Lovemyhardbody is offline   Reply With Quote
Old 12-29-2016, 11:28 PM   #2
ahardb0dy
The Post Count Whore
 
ahardb0dy's Avatar
 
Join Date: May 2014
Location: Sorrento, Florida
Age: 54
Posts: 7,678
Vehicle: 2017 Nissan Frontier Desert Runner
Thanks: 66
Thanked 939 Times in 860 Posts
Default

1 wire goes to the battery and the other goes to the bulb check relay which feeds the charge light
__________________
My name is Tony and I'm a Infamousaholic

Current truck - 2017 Nissan Frontier Desert Runner ,

(formerly owned: 1993 Nissan Hardbody king cab 2wd, 90 Nissan Sentra, 94 Nissan Pathfinder SE 4x4, 05 Nissan Titan, 87 Nissan SE-V6 4x4 king cab, 94 Infiniti Q45t & 80 Datsun 310GX )
ahardb0dy is offline   Reply With Quote
Thanked by:
Lovemyhardbody (12-29-2016)
Old 12-29-2016, 11:29 PM   #3
Lovemyhardbody
 
Lovemyhardbody's Avatar
 
Join Date: Nov 2016
Location: TX
Posts: 18
Vehicle: 90 Nissan d21
Thanks: 11
Thanked 0 Times in 0 Posts
Default

Also noticed a loose wire coming thru the main harness from the check relay on the passenger wheel well...

It isn't connected anywhere but when it's touched to the negative terminal the relay makes a click noise...

Is there a diode that is supposed to be connecting the two?
Lovemyhardbody is offline   Reply With Quote
Old 12-29-2016, 11:33 PM   #4
ahardb0dy
The Post Count Whore
 
ahardb0dy's Avatar
 
Join Date: May 2014
Location: Sorrento, Florida
Age: 54
Posts: 7,678
Vehicle: 2017 Nissan Frontier Desert Runner
Thanks: 66
Thanked 939 Times in 860 Posts
Default

would need more info on the other wire, exact location, color
__________________
My name is Tony and I'm a Infamousaholic

Current truck - 2017 Nissan Frontier Desert Runner ,

(formerly owned: 1993 Nissan Hardbody king cab 2wd, 90 Nissan Sentra, 94 Nissan Pathfinder SE 4x4, 05 Nissan Titan, 87 Nissan SE-V6 4x4 king cab, 94 Infiniti Q45t & 80 Datsun 310GX )
ahardb0dy is offline   Reply With Quote
Thanked by:
Lovemyhardbody (12-29-2016)
Old 12-29-2016, 11:35 PM   #5
Lovemyhardbody
 
Lovemyhardbody's Avatar
 
Join Date: Nov 2016
Location: TX
Posts: 18
Vehicle: 90 Nissan d21
Thanks: 11
Thanked 0 Times in 0 Posts
Default

Quote:
Originally Posted by ahardb0dy View Post
would need more info on the other wire, exact location, color
Sorry- the wire is coming out if the check relay and it goes thru the main harness connector @ the battery it's yellow with black stripe
Lovemyhardbody is offline   Reply With Quote
Old 12-29-2016, 11:57 PM   #6
Lovemyhardbody
 
Lovemyhardbody's Avatar
 
Join Date: Nov 2016
Location: TX
Posts: 18
Vehicle: 90 Nissan d21
Thanks: 11
Thanked 0 Times in 0 Posts
Default

I am learning how to follow the wiring diagrams and I'm pretty sure there should be a diode. But I've been wrong before and my wires have been 'altered' in the past. So I just wanted to double check...

The missing diode is what regulates the alternator charge? So without it there is no link between the relay and the alternator to tell the computer whether the alternator is producing enough current and charging the battery properly?
Lovemyhardbody is offline   Reply With Quote
Old 12-30-2016, 03:23 AM   #7
alabama_lowlife
Owner and Administrator
 
alabama_lowlife's Avatar
 
Join Date: Sep 2008
Location: jack, alabama
Age: 41
Posts: 10,205
Vehicle: 2012 370Z, 1970 Datsun 521, 1995 Nissan Hardbody x2
Thanks: 923
Thanked 2,003 Times in 1,649 Posts
Default

The alternator is internally regulated. It senses the battery's state of charge through the small white wire.

The yellow wire is the wire that provides excitation for the alternator. It comes through the instrument cluster battery light and the alternator provides a ground to illuminate the light. Once the alternator starts charging the ground is removed and the battery light goes off.
__________________
alabama_lowlife is offline   Reply With Quote
Old 12-31-2016, 03:07 PM   #8
Lovemyhardbody
 
Lovemyhardbody's Avatar
 
Join Date: Nov 2016
Location: TX
Posts: 18
Vehicle: 90 Nissan d21
Thanks: 11
Thanked 0 Times in 0 Posts
Default

So what would the yellow wire be connected to? Cuz mi e is just hanging there... In the diagram it shows it going to a diode and then thru harness to the check relay
Lovemyhardbody is offline   Reply With Quote
Old 12-31-2016, 03:29 PM   #9
cadillacdude1975
The Gear Jammer
 
cadillacdude1975's Avatar
 
Join Date: Apr 2013
Location: Chattanooga, TN
Age: 48
Posts: 10,023
Vehicle: 87 D21 SE KC V6 2wd 5sp & 87 Pathfinder 4x4 SE
Thanks: 399
Thanked 1,216 Times in 1,118 Posts
Default

does the battery light stay on all the time?
cadillacdude1975 is offline   Reply With Quote
Old 12-31-2016, 03:30 PM   #10
cadillacdude1975
The Gear Jammer
 
cadillacdude1975's Avatar
 
Join Date: Apr 2013
Location: Chattanooga, TN
Age: 48
Posts: 10,023
Vehicle: 87 D21 SE KC V6 2wd 5sp & 87 Pathfinder 4x4 SE
Thanks: 399
Thanked 1,216 Times in 1,118 Posts
Default

cadillacdude1975 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 03:26 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.