Conversions & Swaps LSX Engines in Non-LSX Vehicles
Sponsored by:
Sponsored by:

The time has come to start asking questions...

Thread Tools
 
Search this Thread
 
Old Sep 16, 2013 | 06:36 PM
  #1  
FEAR LS's Avatar
Thread Starter
10 Second Club
iTrader: (8)
 
Joined: Nov 2011
Posts: 468
Likes: 0
From: California
Default The time has come to start asking questions...

I'm dealing with a 2002 LS1 wiring harness. I have power to the PCM and proper grounds. (Checked this with a multimeter at the proper pinouts, using this diagram http://www.ls2.com/boggs/torques/2002pcm.htm) I am using a battery charger to test the power and grounds 12v 6amp setting. (Grounds go to black cable, Constants go to the Red cable, and a switch wired up for my Ignitions<-- This may not even be necessary but I cannot seem to get HPTuners or my OBD II scan tool to read. I continue to get the "make sure key is on" display) I have the harness out and on the floor (Much easier to test, instead of laying on a roll cage and my body bent like a pretzel halfway into the car) so nothing is fused or on relays just yet. I wanted to test the harness/PCM/OBD II prior to installing it into the car.

Blue connector: Pins 2,19,20,57 all have 12v while 1, and 40 are grounded. Pin 58 is hooked up to my OBD II Port.

Red Connector: Pins 1, and 40 are grounded and Pin 39 has 12v

My questions are:
Is there anything else that requires power besides the "Orange and Pink" wires or the ones I mentioned above?
Would my battery charger give it the proper grounding it needs? It reads fine, but may not be strong enough?
Are VATS an issue at this point (Testing harness)?
Am I missing a 5v reference?
Reply
Old Sep 16, 2013 | 09:28 PM
  #2  
Pocket's Avatar
TECH Addict
15 Year Member
iTrader: (22)
 
Joined: Apr 2009
Posts: 2,656
Likes: 149
From: NC
Default

Use a battery hooked to the charger for the tests

B2 and R39 are crank and cam sensor 12v. Not required for testing power

B19 must be on a switch while B20&57 constant for the scanner to function. If that's the case, test the grounds and serial circuit

Personally, I prefer ohming out each circuit instead of doing power/function tests. Much faster

VATS will not prevent your scanner from functioning. It only disables the starter and fuel system
Reply
Old Sep 16, 2013 | 09:58 PM
  #3  
bczee's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (12)
 
Joined: Jan 2006
Posts: 6,670
Likes: 6
From: Concord, CA
Default

did you wire up Battery power to the ODBII connector port ?
Reply
Old Sep 16, 2013 | 10:09 PM
  #4  
FEAR LS's Avatar
Thread Starter
10 Second Club
iTrader: (8)
 
Joined: Nov 2011
Posts: 468
Likes: 0
From: California
Default

Originally Posted by Pocket
Use a battery hooked to the charger for the tests

B2 and R39 are crank and cam sensor 12v. Not required for testing power

B19 must be on a switch while B20&57 constant for the scanner to function. If that's the case, test the grounds and serial circuit

Personally, I prefer ohming out each circuit instead of doing power/function tests. Much faster

VATS will not prevent your scanner from functioning. It only disables the starter and fuel system
Thanks a lot man. I'll give it a try when I get home from work. Ohming is much faster, but I want to get HPTuners to load up before I install the harness. I will also put a battery/charger on it instead of charger alone.

Those wires hooked up alone will let the PCM start talking to the scanner?

Originally Posted by bczee
did you wire up Battery power to the ODBII connector port ?
Yes, has sufficent battery power and ground.
Reply
Old Sep 16, 2013 | 10:35 PM
  #5  
i r teh noobz's Avatar
TECH Resident
iTrader: (4)
 
Joined: Feb 2009
Posts: 784
Likes: 0
From: Ohio
Default

You only need a couple power wires and a data line to get the scanner hooked up. I made a PCM test harness, I think it has 3 or 4 power wires (been a while since I used it).
Reply
Old Sep 17, 2013 | 07:53 AM
  #6  
Pocket's Avatar
TECH Addict
15 Year Member
iTrader: (22)
 
Joined: Apr 2009
Posts: 2,656
Likes: 149
From: NC
Default

http://www.thirdgen.org/techboard/lt...t-lsx-pcm.html

That's all that's needed to power up a PCM
Reply
Old Sep 17, 2013 | 01:58 PM
  #7  
FEAR LS's Avatar
Thread Starter
10 Second Club
iTrader: (8)
 
Joined: Nov 2011
Posts: 468
Likes: 0
From: California
Default

Thanks guys! I'm home from work now, I'm going to try what Pocket has posted and see where we are from there. I'll give you guys an update once I get it.
Reply
Old Sep 17, 2013 | 02:49 PM
  #8  
FEAR LS's Avatar
Thread Starter
10 Second Club
iTrader: (8)
 
Joined: Nov 2011
Posts: 468
Likes: 0
From: California
Default

That worked! Hell Yes!! I'm able to communicate with the PCM via HPTuners and my scan tool. My only problem now is I went to "read entire" in editor. It gave me the loc:4000 Checksum fail. So I guess the PCM will need re-flashing back to stock with a tech2.

Pocket: Could you hook me up with what needs to be hooked up so I can have the engine run. Or if the PCM is powered I'm good to go? I seemed to have stepped back to square one. The pcm is good to go now, I'm ready to install it into the car. I would just like to know what else needs to be powered for the harness to function properly.

Thanks guys!
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo




All times are GMT -5. The time now is 06:23 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE