pulling codes on a "90"?
Le Mans Master
Joined: Mar 1999
Posts: 9,663
Likes: 1,682
From: Fort Worth Texas
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Former Moderator
Cruise-In I-II-III Veteran
use a paper clip and jump connections A and B on the ALDL under the drivers side area.
Turn the key on and the check engine light will flash in morse code... a 12 is normal, it means it's working. to flash a 12 it will flash the check engine light once, then twice. It will repeat each code three times...
so if you had a code 34 the check engine light would flash like this after turning the key on:
Flash - Flash Flash (this is the 12, the - is a slight pause)
Flash - Flash Flash
Flash - Flash Flash
Flash Flash Flash - Flash Flash Flash Flash
Flash Flash Flash - Flash Flash Flash Flash
Flash Flash Flash - Flash Flash Flash Flash
Flash - Flash Flash
Flash - Flash Flash
Flash - Flash Flash
go give it a try and you'll see.... a service manual sounds like a good addition to your library, it has all kinds of cool stuff like this in there.
It will repeat between the 12 and the other codes until you pull the connector or turn the key off. The fan running while you do this is normal as well.
Turn the key on and the check engine light will flash in morse code... a 12 is normal, it means it's working. to flash a 12 it will flash the check engine light once, then twice. It will repeat each code three times...
so if you had a code 34 the check engine light would flash like this after turning the key on:
Flash - Flash Flash (this is the 12, the - is a slight pause)
Flash - Flash Flash
Flash - Flash Flash
Flash Flash Flash - Flash Flash Flash Flash
Flash Flash Flash - Flash Flash Flash Flash
Flash Flash Flash - Flash Flash Flash Flash
Flash - Flash Flash
Flash - Flash Flash
Flash - Flash Flash
go give it a try and you'll see.... a service manual sounds like a good addition to your library, it has all kinds of cool stuff like this in there.
It will repeat between the 12 and the other codes until you pull the connector or turn the key off. The fan running while you do this is normal as well.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
1) Pencil & Paper At The Ready
2) Key Off
3) Short Pins A&B OnThe ALDL
4) Key On (Do NOT Start The Engine)
5) Count the Flashes (Check Engine Light) & Write Them Down
6) Key Off
7) Unshort Pins A&B On The ALDL
The First Three Flashes Will Be 12,12,12,
Followed By Three Flashes Of Any Stored Codes
Finished By 12,12,12
If all you get are 12's then you have no MIL Codes Stored.
Example: Code 32 Stored:
12,12,12 32,32,32 12,12,12
Do a search for ODBI codes to decode the ones, if any, you have.
Or post them here.
2) Key Off
3) Short Pins A&B OnThe ALDL
4) Key On (Do NOT Start The Engine)
5) Count the Flashes (Check Engine Light) & Write Them Down
6) Key Off
7) Unshort Pins A&B On The ALDL
The First Three Flashes Will Be 12,12,12,
Followed By Three Flashes Of Any Stored Codes
Finished By 12,12,12
If all you get are 12's then you have no MIL Codes Stored.
Example: Code 32 Stored:
12,12,12 32,32,32 12,12,12
Do a search for ODBI codes to decode the ones, if any, you have.
Or post them here.
