2nd Gen Ram Tech 1994-2001 Rams: This section is for TECHNICAL discussions only, that involve the 1994 through 2001 Rams. For any non-tech discussions, please direct your attention to the "General discussion/NON-tech" sub sections.

2000 5.9L 2500 4x4 ignition coil question

Thread Tools
 
Search this Thread
 
Old Apr 16, 2021 | 03:08 PM
  #1  
rgedye's Avatar
rgedye
Thread Starter
|
Registered User
Joined: Apr 2021
Posts: 3
Likes: 0
Default 2000 5.9L 2500 4x4 ignition coil question

While diagnosing my no-start condition on my truck that has been stored indoors for many years; I have resolved a few issues.
Currently [after replacing CKP] I am showing no trouble codes [formerly P0320 & P1282].

My specific question is this - Should I be able to 'prove' coil ground feed [black] has proper ground by observing 12V from ground lead to POS Battery terminal with key-on?
I know the voltage readings for the 12+ lead to coil and injectors, and that it should initially show +12V on key-on, then drop to zero, then show +12v upon cranking.
I have confirmed this proper operation. I also understand that the coil receives it's ground via a lead rather than chassis ground.

However, in trying to resolve problem in no-start [before my spark and fuel pressure testers arrive as ordered], I DO NOT see what I thought I should concerning this coil connection.
I observed [oddly] ~ 0.5v on this black coil signal lead across to POS battery post with key off; then only a similar small voltage with key-on [not crank].

Again, after initially resetting the trouble codes through battery disconnection after replacing Crank Position Sensor [CKP], no codes are now listed.
I'm assuming the P1282 fuel system code was initially set after many times of cranking with a bad CKP.
When originally resetting codes prior to CKP replacement, P1282 disappeared and only P0320 re-appeared. The replacement of the CKP removed the P0320 code.

Any help would be appreciated. I have replaced the coil assembly to no change.

 
Reply
Old Apr 16, 2021 | 05:02 PM
  #2  
HeyYou's Avatar
HeyYou
Administrator
Veteran: Air Force
Community Favorite
15 Year Member
Community Builder
Joined: Apr 2010
Posts: 87,453
Likes: 4,218
From: Clayton MI
Default

If you only have the meter, put it on 20V, red goes to positive, black lead goes into the ground side of the connector for the coil, and have someone crank the engine. Should see voltage switching from 12 to 0 fairly reliably. Trouble is, a digital meter may not react fast enough.... An easier test, if you have a test light..... is to put the test light across the terminals in the coil connector (harness side) and crank the engine. Light should flash.
 
Reply
Old Apr 18, 2021 | 12:21 PM
  #3  
rgedye's Avatar
rgedye
Thread Starter
|
Registered User
Joined: Apr 2021
Posts: 3
Likes: 0
Default

Thank you. When re-reading the service manual, I realized that this is a switched line rather than constant.
The tip on using a test light is a good one.
 
Reply
Old Apr 24, 2021 | 05:55 PM
  #4  
rgedye's Avatar
rgedye
Thread Starter
|
Registered User
Joined: Apr 2021
Posts: 3
Likes: 0
Default

Update & resolution -
After pick-probing the Black signal/ground wire to the coil with a test light to battery positive & seeing proper signal, I was stumped for a moment; then I tested continuity from my pick probe to connector and found it open & providing no signal to coil.

This fixed the problem - https://www.rockauto.com/en/moreinfo...454&cc=1362013
 
Reply
Old Apr 25, 2021 | 09:43 AM
  #5  
HeyYou's Avatar
HeyYou
Administrator
Veteran: Air Force
Community Favorite
15 Year Member
Community Builder
Joined: Apr 2010
Posts: 87,453
Likes: 4,218
From: Clayton MI
Default

Awesome.
 
Reply




All times are GMT -4. The time now is 07:32 AM.