NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > OEM Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

OEM Tech Discussion Forum for OEM (Original Equipment) or stock XJs and MJs.

Reply
 
Thread Tools Display Modes
  #1  
Old June 1st, 2006, 19:54
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Angry No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

I am not getting any spark on my 95' XJ.
Replaced my CPS, ECU unit, ASD relay, checked my coil, coil is fine but nothing is going to the coil.
So from what I understand, the The green/orange wire that gos to the coil is fed from the ASD relay (automatic shut down relay), replaced that relay, still no luck. So i guess im down to the PCM? (Powertrain Control Modual).
My book tells me that from 91' to 98' XJ's are epuiped with a Powertrain Control Modual. They must have skipped 95' because I cant seem to locate it from where my book tells me it is!!??
The PCM is apparently is what feeds the relays. Where is the PCM located on my 95? my book shows it locted on the firewall from 91' to 98'....
Reply With Quote
  #2  
Old June 1st, 2006, 19:59
lilredwagn lilredwagn is offline
NAXJA Forum User
 
Join Date: Jul 2005
Location: South Carolina
Posts: 509
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Your PCM is the "computer" that you will also see referred to here as ECM or ECU. It's mounted on the inside fender on the drivers side.
Reply With Quote
  #3  
Old June 1st, 2006, 20:18
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

The ECU, on the inside fender, I have already replaced, brand new. Still no spark. Any other ideas?
Reply With Quote
  #4  
Old June 1st, 2006, 20:20
RyanM's Avatar
RyanM RyanM is offline
NAXJA Forum User
 
Join Date: Jan 2006
Location: va
Posts: 2,793
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

what about fuel??

change out the pick up sensor in the dist. cap...
Reply With Quote
  #5  
Old June 1st, 2006, 20:24
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Quote:
Originally Posted by skyjackedxj96
what about fuel??

change out the pick up sensor in the dist. cap...

Would that have any effect on any power getting to the coil?
Reply With Quote
  #6  
Old June 1st, 2006, 20:29
langer1's Avatar
langer1 langer1 is offline
NAXJA Forum User
 
Join Date: Jun 2005
Location: Mineral City,Ohio
Posts: 5,006
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Quote:
Originally Posted by RubiconXJ90
Would that have any effect on any power getting to the coil?
Yes it could but what code are you getting, a bad CKP will through a code "Lose of sync pulse or something.
Reply With Quote
  #7  
Old June 2nd, 2006, 16:39
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Quote:
Originally Posted by langer1
Yes it could but what code are you getting, a bad CKP will through a code "Lose of sync pulse or something.
I'm just getting code 12 and 55. 12 meaning that "it was cleared" and 55 meaning "end of message."
Reply With Quote
  #8  
Old June 3rd, 2006, 18:21
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Another thing that I'm thinking it could be is the ignition switch, I've started to notice that I have to turn the key more than once to get the engine to turn over. Anyone ever have this problem? (95 XJ airbag steering column)
I've gone over EVERYTHING on the engine that could cut out power to the coil... and I'm just getting code 12 and 55.
The only sensor that I haven't to replace is the knock sensor, but that should show code 16 for open or short.
Is the ignition switch testable once removed?

did I mention that I hate electrical...? yea... I hate electrical!
Reply With Quote
  #9  
Old June 5th, 2006, 17:18
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

come on guys... someone must know some sort of an answer!?
Reply With Quote
  #10  
Old June 5th, 2006, 18:45
lilredwagn lilredwagn is offline
NAXJA Forum User
 
Join Date: Jul 2005
Location: South Carolina
Posts: 509
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Quote:
Originally Posted by RubiconXJ90
come on guys... someone must know some sort of an answer!?
What were you doing when the jeep failed? What maintenance had you performed directly prior to the jeep failing?

Start over.

Check all your fuses, both under the dash and in the PDC under the hood. Don't just glance from the top, pull them, look at them from the side.
Reply With Quote
  #11  
Old June 5th, 2006, 21:14
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Quote:
Originally Posted by lilredwagn
What were you doing when the jeep failed? What maintenance had you performed directly prior to the jeep failing?

Start over.

Check all your fuses, both under the dash and in the PDC under the hood. Don't just glance from the top, pull them, look at them from the side.
The jeep just came to a dead stall while I was taking a left from a left turn lane. Wouldnt start back up, noticed that it was no longer getting spark, no power to the coil. It was running smooth before hand.
I have gone thoroughly over ALL the fuses over and over again.
Replaced the Crank Shaft positioning Sensor, ECU, ASD relay, camshaft modual, rotor/cap, spark plug wires, checked the coil at an auto supply shop, checked the timing chain, just today I replaced the Ignition switch because the old one I had to either hold the key in the start position for 1 to 3 seconds or turn it more than once before the engine would even crank, But whats funny is that new one still dose the same...?
I am still only getting code 12 and 55.
Reply With Quote
  #12  
Old June 5th, 2006, 21:35
RubiconXJ90 RubiconXJ90 is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: Tacoma, WA
Posts: 26
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Should I try fixing it with a stick of dynamite?
Reply With Quote
  #13  
Old June 5th, 2006, 21:51
lilredwagn lilredwagn is offline
NAXJA Forum User
 
Join Date: Jul 2005
Location: South Carolina
Posts: 509
Re: No spark, replaced CPS, ECU, ASD relay... nothing getting to the coil

Alright, fuses are check.

I'm reading from my 96 FSM, fwiw.

Disconnect the coil from the harness (the supply side, not the spark side) and use a couple short pieces of wire to jump the connection. (this is so that you can get a probe onto the circuit without breaking the connector open)

Turn the ignition to "on" (not start)

Use a voltmeter. Touch the voltmeter negative to vehicle ground and probe the right hand wire (as you face the vehicle from the front) with the positive lead on the voltmeter. You should get 12.4 or greater volts. If you get nothing, try the wire on the other side.

Once you've found the wire with 12v on it, have someone crank the engine for 5 seconds while you monitor the voltage reading.

While cranking, does the voltage:
-stay at or near zero for all 5 seconds
-stay at 12v for 1-2 seconds and then drop to zero
-stay at or near 12v for entire length of cranking

?
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
HELP! no spark at coil redXJay OEM Tech Discussion 26 June 1st, 2006 19:55
Spark plugs/cap and rotor/coil?? Mercenary OEM Tech Discussion 0 December 30th, 2005 22:24
no spark at coil 90 xj OEM Tech Discussion 0 December 30th, 2005 19:05
No Spark off Coil XJZ OEM Tech Discussion 9 April 3rd, 2005 00:04


All times are GMT -7. The time now is 04:18.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014