Thread: Ls alt wiring
View Single Post
Old 03-02-2015, 12:53 PM   #58
Pzary3233
Registered User
 
Join Date: Apr 2012
Location: Memphis, TN
Posts: 65
Re: Ls alt wiring

Quote:
Originally Posted by mattcrp1 View Post
Sorry, I have a 2002 4.8l in my 1976 SWB. The 2002 appears to be "self contained" as far as what I need to do with integrating the 1976 and 2002 harnesses. I also have a question as to the blue oil pressure switch wire from the '76 harness as well.
You will not use any of the wiring from the original 76 truck except for the GEN light which will be needed to put a slight resistance on the wire.

Assuming that you have a truck alternator this is what you need to do - Copied from what I posted on the first page:

One wire goes straight to 12 volt (Pin C), the other MUST have resistance, ie gen light or resistor (Pin B)..





However as LS1Nova pointed out you can easily just leave the two wires connected to the PCM and let the PCM worry about the Alternator


Quote:
Originally Posted by ls1nova71 View Post
You can just eliminate any of the original '76 alternator wiring, it is self contained on the 2002 like you said.

As for the blue wire for the '76 oil pressure gauge, you need to mount the '76 oil pressure sender in either the oil pressure sender spot of the 5.3, or you can drill and tap the block off above the oil filter, then just hook the blue wire to it and you're done.
This is correct, you need to use your original sending unit, or another sending unit that fits in the LSx with the same output as the original 76 sending unit.
__________________

'55 3200 283 4 speed
'68 Pontiac Firebird Poncho powered with a 6 speed

Last edited by Pzary3233; 03-02-2015 at 01:02 PM.
Pzary3233 is offline   Reply With Quote