`90 flashing sys question
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
Likes: 0
From: richardson tx
`90 flashing sys question
i was looking for a 12v source close to where i was working ( fan relay ) area. found 2 with my volt meter. one was a black and yellow wire running to the fan relay and the other was right above the canister next to the driver side head light pocket it was a 2 wire plug dont really know what info it provided to the ecm or ccm. anyhow i tried to tie into both sources no luck i mean the the current would drop on each. then when i went back to check them with the meter they were hardly showing any current. oh yea i was looking for a hot wire for my new fan relay switch. i guess the draw was to much? now the speedo does not work with the sys flashing next to it. the led lights up but stays at 0mph. do you think i fried a fusable link right next to the battery or worse?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
you really need to scan the CCM.
C4 Guru - CCM Code Reading 1992/1993
I know that is aimed at the 1992/1993, but the procedures are the same.
return any codes to us for translation, if they are not listed in the Tech Tip.
C4 Guru - CCM Code Reading 1992/1993
I know that is aimed at the 1992/1993, but the procedures are the same.
return any codes to us for translation, if they are not listed in the Tech Tip.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
Likes: 0
From: richardson tx
Originally Posted by bogus
you really need to scan the CCM.
C4 Guru - CCM Code Reading 1992/1993
I know that is aimed at the 1992/1993, but the procedures are the same.
return any codes to us for translation, if they are not listed in the Tech Tip.
C4 Guru - CCM Code Reading 1992/1993
I know that is aimed at the 1992/1993, but the procedures are the same.
return any codes to us for translation, if they are not listed in the Tech Tip.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
Likes: 0
From: richardson tx
Originally Posted by bogus
with all the EFI stuff gone, I would wonder if enough data is being made available.
It sounds to me like an "all bets are off" situation.
It sounds to me like an "all bets are off" situation.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
Likes: 0
From: richardson tx
replaced the ecm today. no good. the sys is still flashing on the upper left of the lcd. still no mph. the chain of command is the vss sends the sig to the ecm, the ecm sends it to the ccm, the ccm sends it to the lcd. beam me up scotty?. the signal gets flipped and flopped interperted and changed so all those involved during the process can read it and pass it on. the ccm operates other stuff as well interior lighting ect.... which i still have among others. did i fry the vss link or the sensor its self? have you ever seen the sys flashing in the lcd on a `90?
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Drifting
Joined: May 2003
Posts: 1,979
Likes: 48
From: Lakeport CA
I've had SYS on my 90 but only with low battery voltage & also when I have my laptop & Moates software running. It will pop up about every 30 seconds or so. Not sure if it has to do with running in diagnostics mode or what??
Thread Starter
Burning Brakes
Joined: Jun 2004
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From: richardson tx
Originally Posted by Trog
I've had SYS on my 90 but only with low battery voltage & also when I have my laptop & Moates software running. It will pop up about every 30 seconds or so. Not sure if it has to do with running in diagnostics mode or what??
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
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From: richardson tx
fyi. checked the codes stored with in the ccm and the ecm by jumping the aldl. first code flashed was c-41 loss of ecm serial data communication. so i read on and will be doing the continuity check of the wires discribed in the books between the ecm and ccm. hopefully i will find or spot a burned wire. iv ruled out the ecm since the one i have is new as well as the ccm cause eveything else related is working. anybody pulled out the ccm? the book says its behind the radio center of dash. looks like an ordeal.
Racer
Joined: Apr 2005
Posts: 408
Likes: 0
Are you still using your ecm for anything? Also, I was wondering, if you no longer use the ecm to control the motor, are all the plugs still running somewhere, or are they taped up? Could one of them shorted to ground and fried the wiring from your ecm to the engine?
Last edited by lt4red; Mar 13, 2006 at 12:27 AM.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
Likes: 0
From: richardson tx
Originally Posted by lt4red
Are you still using your ecm for anything? Also, I was wondering, if you no longer use the ecm to control the motor, are all the plugs still running somewhere, or are they taped up? Could one of them shorted to ground and fried the wiring from your ecm to the engine?
