I have seen several references to "I read a code #_____" in trouble shooting. How does one get the code? Is there a read-out tool you can buy? And is it Mucho$$$$ ? Also, what is "the paper clip trick"?

Verne :seeya
:cheers:

 

Any good car parts store will sell you a little plastic plug in device that plugs in to the ALDL (assembly line diagnostic link) located just under the dash a little to the right of the steering colune, you shut the car off, plug it in, and turn the key to on but DONT START IT! This will make the service engine soon light start to blink. It will blink number 12 three times and then pause and then it will blink the number of any stored codes. The way it blinks the numbers is twelve would be like this: blink, pause, blink blink,,,,,,blink, pause, blink bling,,,,,, So a code 32 (rather common) would blink like this: blink blink blin, pause, blink blink,,,,,,, It will blink any stored codes 3 times for each code and then there will be a long pause and it will start over with code 12 three times, then stored codes. The code 12 just blinks to show that you have hooked it up right. I bought the plug because for about $30 you get the plug and a nice book that lists just about every GM code for every pre-96 GM car. Also, by sticking the plug in and turning on the key it turns on your cooling fan. So make sure you are clear of the fan when you do this. You can get a little jumper key for about $2 that does the same thing but not quite as easy to plug in when you are sitting in the driver's seat waiting to make your next run at the track, and you don't get the code book.

 

Bend a #1 paper clip into a "U" and insert into ALDL pins A & B (the two on the upper right). Turn On the ignition and count the flashes. You have all the codes when the second set of 3 "12" has flashed.

Give it a try. If you have no trouble codes stored of course it will flash up 3 12s followed by 3 more 12s.

This all assumes you have an OBD-I setup. What year is your Vette??


[Modified by 65Z01, 9:40 PM 12/17/2001]

 

Got a 1990 Coupe, and our first Vette. Thanks loads for the info.
Verne :cheers: :seeya :reddevil

 

Good, this method will work for you.

BTW, if you have any trouble codes you will need to reset the ECM. This is done by removing power to the ECM for about 1 minute. Either disconnect a battery lead (which will reset your radio and clock) or better open the connector in the orange wire comming from the battery (this lead supplies power only to the ECM).


[Modified by 65Z01, 12:32 AM 12/18/2001]

 

Will this work for a '95 LT1 also?

 

Thumper,
That will not work on a 95.

 

82 to 89 jump A to B and read flash codes, 90 to 93 jump A to G(top right and bottom left) and watch speedo and you can read ECM,CCM, ABS and more depending on which year and options 1.1 CCM, 4.1 ECM 9.1 ABS/ASR,
94 and 95 jump 4 to 12(4th from left on top and the one under) and with the key on engine not running watch speedo you can do the same with a 96 but you will not get ECM codes that you need an OBDII scanner.

David Fulcher

 

Thanks David. I have a code I need to go read.

 

I have always used a paperclip bent into a "U" shape. Works fine and costs next to nothing. For a info on what the codes mean check out the following:
http://members.tripod.com/theviperpi.../ecmcodes.html
http://members.tripod.com/theviperpit/vette/ecm.html

 

Where is the orange wire on an 88? Is it fused in the fuse panel? Is it hot all the time?
Thanks
Harold

 

That orange wire is fused by the ECM power fuse. The in-line connector is rather close to the battery so that it's easier to open than to get at the fuse panel.

 

Guys,

this is very helpful. I have no experience pulling codes like this. However I have a 1996 LT4 which is I believe OBDII. Can you give me a little quick tutorial similar to this one for OBDII? How do I go about pulling codes for this system? Is the the plug-in similar? Is the "blink" method the same?

Any help is appreciated.

 

I don't think the "blink" method works on OBD II. OBD II has many more "trouble code" possibilities than OBD I. It would be very easy to loose count as it flashed or more 120 times for just one code!

You might want to try this web site that offers a "freeware" package for down loading the OBD II codes to a computer:

http://www.blacky.co.nz/efilive/


I haven't tried it yet but the interface is very simple and the "Read Me" file gives a list of what all the codes mean.


[Modified by Wildride, 10:24 AM 12/20/2001]

 

96 and up use a letter and three number trouble code system it's part of the OBDII fed. mandate system do you can not flash codes and because the LCD is not able to desplay that you are unable to pull ECM codes on a 96 through the CCM you need a scanner to get codes with the 81 to 93 vette you can jump the A to B terminals of the ALDL connector and watch the "service engine soon" light you could flashes in between pauses 1 flash followed by short pause then two flashes then a longer pause would give you code 12 this would happen three times then a long pause and if it were to repeat no more codes but if there were other codes they would follow.

David Fulcher