Which pins going to the ECU should be hot with the key on? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > Which pins going to the ECU should be hot with the key on?

TJ, YJ & LJ Drop Down Tail Gate Conversion KitGreat prices on seating!--Oconee Off-RoadTJ 5.25" Speaker Adapters - NalinMFG

Reply
Unread 09-01-2011, 04:37 PM   #1
AnonymousD
Registered User
1992 YJ Wrangler 
 
Join Date: Jul 2010
Location: Louisiana
Posts: 903
Which pins going to the ECU should be hot with the key on?

Im trying to track down the problem in my '92 4.0L. I tested all the pins and I get 12V on only the #3 pin. All the other pins are dead with the key on.

This is of course, with the computer out of the vehicle.

AnonymousD is offline   Reply With Quote
Unread 09-01-2011, 05:01 PM   #2
kloppk
Registered User
1992 YJ Wrangler 
 
Join Date: Oct 2006
Location: Massachusetts
Posts: 2,693
Pin 9 should get 12 v from the ignition switch with the key in the Run position.

Pin 3 should have 12 v on it all the time regardless of the key position.
__________________
Baystate Jeepers
Deep Woods Extreme
New England 4 Wheelers
kloppk is offline   Reply With Quote
Unread 09-01-2011, 05:07 PM   #3
AnonymousD
Registered User
1992 YJ Wrangler 
 
Join Date: Jul 2010
Location: Louisiana
Posts: 903
Ok. So looks like it is probably my ignition switch then. Im getting 12V to pin 3 at all times, but nothing to pin 9 with the key on or off.

Sound about right?
AnonymousD is offline   Reply With Quote
Unread 09-01-2011, 05:12 PM   #4
oldtime_ironman
Web Wheeler
1991 YJ Wrangler 
 
Join Date: Dec 2010
Location: 14304 Niagara Falls, NY
Posts: 2,540
I think this link probably explains all of it. He has all that info in his write-up.

http://www.jeepforum.com/forum/f12/9...plained-490788

But yeah that would explain a lot about your ECU if only pin 3 is getting it.

.
oldtime_ironman is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.