General Tech Help Good at troubleshooting? Have a non specific issue? Discuss general tech topics here.

90 accord ECU help

Thread Tools
 
Search this Thread
 
Old Jan 18, 2011 | 06:20 PM
  #41  
TexasHonda's Avatar
Super Moderator : And A Texan
Joined: Feb 2007
Posts: 9,652
From: Katy, TX
Default

You can use a test light to check for voltage at the blk/yel wire at the distributor connector, w/ keyswitch On. If no voltage, the ignition switch assembly has failed.

good luck
 
Old Jan 18, 2011 | 06:44 PM
  #42  
Dannyboi40's Avatar
Thread Starter
|
Member
Joined: Jan 2011
Posts: 124
From: Dirtyburg aka Fredericksburg VA
Default

Im looking at a diagram... shows, Ignigter, coil, and ignition.

I thought the icm, WAS THE COIL, WAS THE IGNITOR... Now I see its not.. crazy how it must sound but I guess i have brain farted, moving to fast.

If the ignition sends power to the ignitor which sends power thru the black and yello wire to coil... maybe the ignitor is messed up??
 
Old Jan 18, 2011 | 07:01 PM
  #43  
PAhonda's Avatar
Super Moderator
Joined: Sep 2006
Posts: 16,331
From: Houston, TX
Default

The ignition switch sends power to both the coil and ICM (aka ignitor).

The ICM gets a signal from the ECU, then the ICM grounds to coil momentarily to allow the coil to charge then discharge a spark.
 
Old Jan 18, 2011 | 07:29 PM
  #44  
Dannyboi40's Avatar
Thread Starter
|
Member
Joined: Jan 2011
Posts: 124
From: Dirtyburg aka Fredericksburg VA
Default

SO... for some reason, someone before I owned the car has grounded the Main relay, by splitting the relay ground, and tapping in a new, seperate wire straight to main relay bolt that hold relay in.

WHY would someone ground the main relay? I have disconected the seperate ground, and to no suprise it wont start at all. Any ideas why someone would have done this?

BTW, the relay looks new, I pulled it apart, and all soders look good. So im not gonna f with it.

On a seperate note, a red wire in the main wire harness looks fried... it looks like it has burnt off its red shielding, and I can see copper wire at least 6 inches worth.. well thats all they have cut into the wire harness... it could extend further into the harness. This is under the dash, above brake pedal, near main relay... and ideas, anyone have this happen to them?

Getting good now ehh..?
 
Old Jan 18, 2011 | 07:31 PM
  #45  
Dannyboi40's Avatar
Thread Starter
|
Member
Joined: Jan 2011
Posts: 124
From: Dirtyburg aka Fredericksburg VA
Default

Originally Posted by PAhonda
The ignition switch sends power to both the coil and ICM (aka ignitor).

The ICM gets a signal from the ECU, then the ICM grounds to coil momentarily to allow the coil to charge then discharge a spark.
THANKS for clearing that up for me! I was going retarded or something.
 
Old Jan 18, 2011 | 07:43 PM
  #46  
10 Gauge's Avatar
Joined: Jan 2011
Posts: 1
From: Fredericksburg, VA
Default

Someone help this poor guy, I've seen him on his back doing more of this....

than anything else.

Here's a picture of the main relay wiring he described....

 
Old Jan 19, 2011 | 05:51 AM
  #47  
TexasHonda's Avatar
Super Moderator : And A Texan
Joined: Feb 2007
Posts: 9,652
From: Katy, TX
Default

Perhaps someone installed a security system which required a separate ground? These have been known to cause starting problems if improperly installed or removed incorrectly.

good luck
 
Old Jan 19, 2011 | 07:17 AM
  #48  
JimBlake's Avatar
Super Moderator
Joined: May 2006
Posts: 18,398
From: Wisconsin
Default

Originally Posted by Dannyboi40
I thought the icm, WAS THE COIL, WAS THE IGNITOR...
The ICM ("ignitor") is a kind of isolation amplifier to prevent any spikes from the coil from getting back to fry the ECU.
 
Old Jan 19, 2011 | 06:48 PM
  #49  
TexasHonda's Avatar
Super Moderator : And A Texan
Joined: Feb 2007
Posts: 9,652
From: Katy, TX
Default

The ignitor serves same function as breaker points on early distributor ignition. It is a switch that allows battery voltage to generate the primary magnetic field, and then opens allowing field to collapse through secondary, and generate a high voltage spark in the secondary coil circuit which in turn generates the spark at the plug.

good luck
 
Old Jan 19, 2011 | 08:55 PM
  #50  
Dannyboi40's Avatar
Thread Starter
|
Member
Joined: Jan 2011
Posts: 124
From: Dirtyburg aka Fredericksburg VA
Default

Low and behold, the blue bandit is ON THE ROAD!! I got a scrap yard ICM, screwed her in... and she is workin great fellas!!

THANKS to all you guys for the help!

I just test drove for over an hour, like 40 miles, and she is runnin strong. Confidence is back jack!!! yet she is 21 years old, im sure ill be back haha
 



All times are GMT -5. The time now is 05:53 AM.