How to pull codes
Thread Starter
Racer
Joined: Dec 2004
Posts: 289
Likes: 3
From: new york
How to pull codes
I did do a search.
I have a 1989 Corvette 6 speed
My Check Engine light is on. I have read peopel pull the codes w/ a paper clip. I would love to do this but have no idea how to. Any help would be appreciated.
I have a 1989 Corvette 6 speed
My Check Engine light is on. I have read peopel pull the codes w/ a paper clip. I would love to do this but have no idea how to. Any help would be appreciated.
Team Owner
Joined: Aug 2004
Posts: 22,300
Likes: 207
From: Sussex,Wi
2023 Corvette of the Year Finalist - Unmodified
2022 C3 of the Year Winner - Unmodified
I got this from a forum I use for my Blazer.
This is for pre-OBDII scan connector equipped GMs
Accessing Trouble Codes
Turn ignition switch to OFF position
Locate the Assembly Line Data Link (ALDL), see image below.
Jumper the A&B terminals(a paper clip or a jumper wire work ok)
Turn Ignition switch to ON position.
Count the flashes on the "CHECK ENGINE" or "SERVICE ENGINE" light.
FLASH, pause, FLASH, FLASH = code 12
12 Pin ALDL
A - Ground
B - Test Terminal
C - Air Injection
E - Serial Data
F - TCC
G - Fuel Pump
H - Brake Sense Speed Input
M - Serial Data
Clearing Trouble Codes
Diagnostic trouble codes may be cleared by disconnecting the battery ground cable for at least 20 seconds. Reconnect negative battery cable and recheck codes to confirm the repair. OBDII can also be reset with a scanner.
This is for pre-OBDII scan connector equipped GMs
Accessing Trouble Codes
Turn ignition switch to OFF position
Locate the Assembly Line Data Link (ALDL), see image below.
Jumper the A&B terminals(a paper clip or a jumper wire work ok)
Turn Ignition switch to ON position.
Count the flashes on the "CHECK ENGINE" or "SERVICE ENGINE" light.
FLASH, pause, FLASH, FLASH = code 12
12 Pin ALDL
A - Ground
B - Test Terminal
C - Air Injection
E - Serial Data
F - TCC
G - Fuel Pump
H - Brake Sense Speed Input
M - Serial Data
Clearing Trouble Codes
Diagnostic trouble codes may be cleared by disconnecting the battery ground cable for at least 20 seconds. Reconnect negative battery cable and recheck codes to confirm the repair. OBDII can also be reset with a scanner.
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
When you use the search function, use it on the main search bar, not in the current section, click Advanced, then in the advanced search box, include 'Archive posts' - that will net you your results...
Just a helpful hint.... good luck
Just a helpful hint.... good luck
Heel & Toe
Joined: Mar 2007
Posts: 24
Likes: 0
From: Ohio
Just to add in there 12 is the base the trouble codes follow so the first code you will see is 12 1 flash pause 2 flash pause which repats for a total of three times. Next comes the trouble code or codes, which repeats three times and you will get the 12 code again at the end. If you can't find a link for the codes just google GM engine scan codes and you should find a listing.
Team Owner
Joined: Jan 2003
Posts: 20,316
Likes: 246
From: Summerland B.C. Canada
Heel & Toe
Joined: Nov 2003
Posts: 18
Likes: 0
From: Lodi Ohio
Thanks, I must have been doing it wrong cause it only gave me two pages and was no help.
