Alternator wiring question 2.5 NAD to 200tdi - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old November 25th, 2009, 11:36 PM
dave_lucas's Avatar
dave_lucas
Status: Offline
Dave Lucas
None
Member
 
Join Date: Sep 2003
Location: CO USA
Posts: 3,126
Alternator wiring question 2.5 NAD to 200tdi

1984 90 2.5 NA Diesel

In the process of installing a Defender 200tdi in my 90 and the alternator connections are different between my 2.5 and the 200tdi

The alternator on my 2.5 has a 3 socket plug with 2 brown wires coming out of it, 1 thick and 1 thin.

The alternator from the Defender 200tdi has the following connection lugs

B+ (Starter positive?)
D+ (Dummy light?)
W (Tach signal?)

Where should I connect the brown wires on the new alternator?

I am guessing that the large brown wire on the existing plug in my 90 should go to B+ on the new alternator????

Thin one maybe to the D+???
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old November 26th, 2009, 02:51 AM
diesel_jim's Avatar
diesel_jim
Status: Offline
Jamie Austin
1992 110 Td5 CSW & 1989 MB G-Wagen
Member
 
Join Date: Oct 2005
Location: Wiltshire, UK
Posts: 1,449
Yeah, you've got it, B+ to the battery, D+ to the dash warning light (thin wire) and W is for a tacho
Reply With Quote
  #3  
Old November 26th, 2009, 11:33 AM
TDI Guy's Avatar
TDI Guy
Status: Offline
Randy
2015 LR4
D-90 Source Vendor
 
Join Date: Sep 2003
Location: NJ
Posts: 4,573
Registry
Dave what year is your truck? Jim is correct. all brown wires to the big lug B+. I think the tach wire is gray?? then the warning light to D+
__________________
Legend in My Own Mind.
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old November 26th, 2009, 01:23 PM
dave_lucas's Avatar
dave_lucas
Status: Offline
Dave Lucas
None
Member
 
Join Date: Sep 2003
Location: CO USA
Posts: 3,126
1984

My Alternator only has 2 wires one thick brown wire and one thin brown wire with a yellow line. There are no other wires from the harness in that area.

The dummy light works but not sure how it gets turned on?

I had planned to run a new wire for the tach
Reply With Quote
  #5  
Old November 26th, 2009, 05:12 PM
dave_lucas's Avatar
dave_lucas
Status: Offline
Dave Lucas
None
Member
 
Join Date: Sep 2003
Location: CO USA
Posts: 3,126
found the wire diagram for my 90 and it shows the large brown wire going to the starter positive and the thin brown / yellow going to the warning lamp.

so....

large brown to B+
thin brown / yellow to D+

need to run a new wire for the tach W
Reply With Quote
  #6  
Old November 26th, 2009, 05:14 PM
Red90's Avatar
Red90
Status: Online
John B.
1991 Defender 90, 200TDI
Site Team
 
Join Date: Sep 2003
Location: Calgary
Posts: 9,233
Registry
You really should replace the brown wire with a larger gauge assuming the alternator is the larger one. Stock wiring is designed for the 45 Amp alternator. Normally there are two heavy brown wires for the 12V and the thin brown/yellow for the charge light. See attached. Alternator is item 35.
Attached Thumbnails
Click image for larger version

Name:	Defender FFR wiring key.jpg
Views:	2053
Size:	202.3 KB
ID:	23251   Click image for larger version

Name:	Defender FFR wiring.jpg
Views:	11647
Size:	249.4 KB
ID:	23252  

Reply With Quote
  #7  
Old December 3rd, 2009, 12:01 PM
dave_lucas's Avatar
dave_lucas
Status: Offline
Dave Lucas
None
Member
 
Join Date: Sep 2003
Location: CO USA
Posts: 3,126
With a last name like Lucas I dare not try to rewire the old harness so I purchased the proper wire harness for a 65 amp 2.5 diesel.

PRC4021

The large brown wire is about 3 X as thick as the one originally in my 1984 90 with 45amp alternator.

Now I have a total of 3 brown wires coming out of the harness for the alternator

Large brown wire with ring connector (goes to B+)
Small brown wire / yellow tracer with ring connector (goes to D+ for dummy light)
Small solid brown wire with plug type connector (??? Maybe B+???)

I assume that the new small solid brown wire with plug also goes to the B+??? Just want to make sure I plug it into the proper place as it is a thin wire and do not want to melt my fancy new wire harness or kill my alternator.

Picture attached of new harness alternator connections

Follow-up Post:

pic of alternator
Attached Thumbnails
Click image for larger version

Name:	65ampharness.jpg
Views:	434
Size:	28.8 KB
ID:	23356   Click image for larger version

Name:	A127-65 (Large).jpg
Views:	2552
Size:	69.8 KB
ID:	23358  

Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
200tdi, alternator, tdi, wiring

Thread Tools

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
200Tdi and LT230 Gear Ratio Question newfD90 Defender Technical Discussions 33 June 1st, 2016 02:30 PM
200tdi oil cooler / oil cooler line thread question dave_lucas Defender Technical Discussions 7 September 26th, 2012 11:56 AM
200tdi Build Question regarding bulkhead fitting Turbofan Defender Technical Discussions 12 October 21st, 2009 01:59 PM
2.5 NAD pump adjustments dave_lucas Defender Technical Discussions 16 September 22nd, 2009 09:40 PM
difference: Disco 200tdi and Defender 200tdi? jaherring Defender Technical Discussions 30 June 3rd, 2005 10:10 AM


All times are GMT -5. The time now is 02:08 PM.


Copyright