1990 diagnostics
Thread Starter
Instructor
Joined: Oct 2000
Posts: 145
Likes: 0
From: Sacramento, CA USA
1990 diagnostics
In my 86, when the "cehck engine" light came on, I knew exactly how to check to codes. In my 1990, the "sys" light flashed several times on the way home. I am guessing I can no longer jump the diagnostic terminal. What tools do I need to buy to work on my new toy?
Anyone remember the number to call to order the GM service manual?
Anyone remember the number to call to order the GM service manual?
Racer
Joined: Sep 2000
Posts: 402
Likes: 0
From: Beaverton OR
Re: 1990 diagnostics (Larry Mackey)
it is the same, if it came on, went off you definatly have a intermentant failure somewhere. if you don't like to use the paper clip for $19.95 you can get a plastic box that snaps in to trigger the SES light & get codes.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Re: 1990 diagnostics (Narnian)
The "SYS" light in the dash is indicative of a CCM error. Many times this is caused by a weak battery. You can still obtain the error codes, but must jump different pins in the ALDL and use the DIC buttons on the side of the instrument panel to obtain the error codes. Unfortunately, I no longed have my 90 manual so I can't be of much help here. Hopefully, someone who does will chime in. First question to ask is, how good is your battery?
Thread Starter
Instructor
Joined: Oct 2000
Posts: 145
Likes: 0
From: Sacramento, CA USA
Re: 1990 diagnostics (vettenuts)
I guess I need to track down a copy of the 90 service manual. I have one of those $5 keys for jumping terminals, but if I need to jump something different I'll need to find out what and go back to the 10 cent paper clip.
I don't know how good the battery is. I just got the car and haven't tested it yet. I have a brand new spare battery from my 86 sitting in the shed. I'm a little worried about swapping the battery though, becuase I've read a few posts where people could not use their radio after making that swap. I'll have to call the PO first and find out if that was ever done.
I don't know how good the battery is. I just got the car and haven't tested it yet. I have a brand new spare battery from my 86 sitting in the shed. I'm a little worried about swapping the battery though, becuase I've read a few posts where people could not use their radio after making that swap. I'll have to call the PO first and find out if that was ever done.
