2nd Generation S-series (1995-2005) Tech Discuss 2nd generation S-series (1995-2005) general tech topics here.

96 blazer replaced valve spring now no fire!

Thread Tools
 
Search this Thread
 
  #11  
Old 07-17-2012, 05:46 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

The Ignition Control Module, ignition coil, and crankshaft position sensor all get voltage from the same fuse on your 1996, (ECM IGN fuse #10, 20 amp fuse in the instrument panel fuse panel). If you don't have voltage at all three, the pink wire is broken somewhere. In a pinch you could run a jumper wire to supply voltage where it's missing.

EDIT: Only way to do the relearn is with a scan tool that can initiate it. The engine might run without doing the relearn, but the data that the PCM uses will be from the last relearn....with the old crank sensor.
 

Last edited by Captain Hook; 07-17-2012 at 05:59 PM.
  #12  
Old 07-17-2012, 06:27 PM
liljde's Avatar
Starting Member
Thread Starter
Join Date: Jul 2012
Posts: 11
liljde is on a distinguished road
Default

Originally Posted by Captain Hook
The Ignition Control Module, ignition coil, and crankshaft position sensor all get voltage from the same fuse on your 1996, (ECM IGN fuse #10, 20 amp fuse in the instrument panel fuse panel). If you don't have voltage at all three, the pink wire is broken somewhere. In a pinch you could run a jumper wire to supply voltage where it's missing.

EDIT: Only way to do the relearn is with a scan tool that can initiate it. The engine might run without doing the relearn, but the data that the PCM uses will be from the last relearn....with the old crank sensor.
so if the ecm and icm have power going to them but not the coil do you think i could just add an external hot going from the fuse to the coil? or what would you do here
 
  #13  
Old 07-17-2012, 06:34 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

If the pink wire at the ignition control module has battery voltage in START and RUN positions, and the ignition coil and crankshaft position sensor do not, you can run a wire from the pink wire at the ICM to the pink wire at the crank sensor & ignition coil.
 
  #14  
Old 07-17-2012, 06:42 PM
liljde's Avatar
Starting Member
Thread Starter
Join Date: Jul 2012
Posts: 11
liljde is on a distinguished road
Default

Originally Posted by Captain Hook
If the pink wire at the ignition control module has battery voltage in START and RUN positions, and the ignition coil and crankshaft position sensor do not, you can run a wire from the pink wire at the ICM to the pink wire at the crank sensor & ignition coil.
ok ty im going to try it right now and ill let you no in abt 10-15 min

ok i had a wire running from the pink wire from the icm to the pink wire on the coil then to the crank sensor and still nothing this has me clueless haha ive never had a 4.3 do this to me
 

Last edited by liljde; 07-17-2012 at 06:51 PM. Reason: tried the steps
  #15  
Old 07-17-2012, 06:57 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

Do you have battery voltage at the ICM, coil, and crank sensor in both start and run positions?
 
  #16  
Old 07-17-2012, 07:12 PM
liljde's Avatar
Starting Member
Thread Starter
Join Date: Jul 2012
Posts: 11
liljde is on a distinguished road
Default

Originally Posted by Captain Hook
Do you have battery voltage at the ICM, coil, and crank sensor in both start and run positions?
ok correction i didnt have to jump the crank sensor it already has power as dose the icm just no power at all to the coil even when i jump the pink wire with the icm there is still no power could it be that the coil pack bracket is not properly grounded on the intake? because with a live hot added to the dead one im still not getting any voltage with the coil pack
 

Last edited by liljde; 07-17-2012 at 07:19 PM.
  #17  
Old 07-17-2012, 07:49 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

The coil does not need to be grounded. The pink wire supplies positive voltage to the coil in the start and run positions. The ignition control module supplies a ground pulse on the white with black stripe wire to fire the coil.

Do you have a test light? If so, connect the ground lead to battery positive and the test light probe to the white with black stripe wire and crank the engine. The test light should blink while cranking.
 
  #18  
Old 07-17-2012, 08:01 PM
liljde's Avatar
Starting Member
Thread Starter
Join Date: Jul 2012
Posts: 11
liljde is on a distinguished road
Default

Originally Posted by Captain Hook
The coil does not need to be grounded. The pink wire supplies positive voltage to the coil in the start and run positions. The ignition control module supplies a ground pulse on the white with black stripe wire to fire the coil.

Do you have a test light? If so, connect the ground lead to battery positive and the test light probe to the white with black stripe wire and crank the engine. The test light should blink while cranking.
with the neg on the posttive batt and the other end on the white wire with black stripes the tester lights up weather the key is on off or cranking
 
  #19  
Old 07-17-2012, 08:24 PM
Captain Hook's Avatar
Moderator
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 8,453
Captain Hook is a jewel in the roughCaptain Hook is a jewel in the roughCaptain Hook is a jewel in the rough
Default

If the light stays on, and doesn't blink while cranking, the ignition control module is not supplying ground to the coil. What you are seeing is the battery voltage going in the coil on the pink wire, and coming out on the white with black stripe. If it doesn't get grounded in the ICM, the light will not blink. Either the ICM is not getting a signal from the PCM telling it to fire the coil, or the ICM can not supply ground to the coil.

The way the ignition circuits work is the crank sensor sends a signal to the PCM, the PCM sends a signal to the ICM on the white wire, and the ICM sends a ground pulse on the white with black stripe wire to fire the coil. There are a couple of things that can cause what you have going on: Could be the ignition control module is faulty, could be a bad ground to the ICM, could be a problem with the crankshaft position sensor, and or its wiring back to the PCM, or, though not likely, a problem with the PCM.

EDIT: Do you have, and know how to use, a digital volt ohm meter?
 

Last edited by Captain Hook; 07-17-2012 at 08:36 PM.
  #20  
Old 07-17-2012, 09:08 PM
liljde's Avatar
Starting Member
Thread Starter
Join Date: Jul 2012
Posts: 11
liljde is on a distinguished road
Default

EDIT: Do you have, and know how to use, a digital volt ohm meter?[/QUOTE]

yes i do and i really appreciate your help ive tried just about everything i even changed the icm and made sure it had a good ground still nothing lol i think im just goinmg to post it on craigslist haha wished i could pay you to come take a look at it xD
 


Quick Reply: 96 blazer replaced valve spring now no fire!



All times are GMT -5. The time now is 02:14 AM.