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· 4x4 v6 blazer
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Discussion Starter · #1 · (Edited)
This seems to keep popping up so I'll make a whole post on this. I know its found all over the net but still we get asked this all the time.

To enter the diagnostics, either connect a scan tool to the ALDL/DLC (thats the plug under the dash on the drivers side) connector or use a jumper wire to connect terminals A and B and begin flash diagnosis.

On carbureted vehicles, the jumper should be connected with the ignition switch turned ON to begin code display.

For fuel injected vehicles, the jumper should be connected with the ignition OFF, then with the jumpers in place, the switch should be turned ON to begin code read out.

In both cases, the engine should NOT BE RUNNING. Once the jumper is properly connected, the control module will enter the diagnostic program and report trouble codes on the scan too or by flashing the SES/check engine light.

All codes are 2 digits between 12 and 82. Codes are displayed on the CHECK ENGINE or SERVICE ENGINE SOON light by flashing the MIL with short and long pauses to distinguish digits of 1 from digits of another.The short pause is used between digits of the same code, long pauses are between codes. For Code 12, the sequence will be: flash, pause, flash-flash, long pause

1. When the diagnostic mode is entered, Code 12 is displayed 3 times. This indicates that the internal diagnostic is operating. If Code 12 is not displayed, the self-diagnostic program is not functioning properly. If no systems malfunctions have been stored, Code 12 will continue to repeat.

On many applications, entering dignostic mode will cause solenoids and relays to activate. Pulse-width modulated solenoids may be rapidly energized and de-engergized, causing a clicking noise. Do not be startled by or concerned with this underhood noise during self-diagnosis code display.

2. After code 12 flashes to indicate diagnostic display, any existing system fault codes are displayed in order from lowest to highest code number. Each code is displayed 3 times, followed by the next code if any.

3. When all codes have been displayed, Code 12 will flash again.


<<<<pics coming in a few minutes as soon as I get off the phone with my wife, if ya'll want this a sticky request it>>>>
 

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #2 ·

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #3 ·
This is a pic of the cheap-o scan tool I have (Had it for years but it was around 20 bucks), a chiltons book which I highly suggest getting if your gonna work on your own truck (also around $20), and I'm using a piece of 14 gauge copper wire to show you how to jump the diagnostic port out (I'm an electrician so I have it laying around but a paper clip is what is normally suggested).

Here are 2 pics of where you need to put the jumper wire if you don't have a scan tool.


 

· Mr. Clean
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839 Posts
Nice article. I'm sure by the end of the weekend though, we'll still have two or three new threads about how to pull an SES code.
 

· Premium Member
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25,691 Posts
done, if there's anything else, PM me for make more sticky, threads into one, etc, anything else relating the topic
 

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #6 ·
Thanks
 

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #8 ·
OBD1 was all the first gens had and since this is in the 60 degree v6 section, which was only offered in first gens.

For obd 2 first I suggest asking in the right section but you have to have a code reader.
 

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #10 ·

· Registered
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Do these trucks store the fault codes (ie will past fault codes that have not been cleared show up)? or do you have to check them when the light is on?


fwiw the vehicle i'm working on is a 2.8 fuel injected model.
 

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #12 ·

· 4x4 v6 blazer
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7,593 Posts
Discussion Starter · #15 ·
don't trash up a sticky with questions, search then start a thread.
 

· .
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3,776 Posts
autozone link no worky anymore. :(
 

· FFAMatt
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196 Posts
Neo could you repost the autozone link? it ain't working anymore
 
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