Hi folks, I'm a newbie to the chevy forums and just recently purchased a 96 blazer for my son. Well, the service engine soon light came on. Already having been familiar with this concept I ran by Autozone to pull the codes.

Here's the problem: When he hooked the ODBII to my blazer it came back with a link error. After trying several times and testing the ODBII on another vehicle we checked fuses and the pins of the connector in my dash. No luck. Anybody out there that can shed some light on what I should do next to get engine codes would be appreciated.

I will attempt to do most of this myself and only take it to a shop when I find that I can't find and/or fix the problem myself.

By the way. It does not seem to be idling rough (vacuum leak), but I'm not going to eliminate anything until I start to hear from some of you veteran owners.

 

hmm..while working as a technician, i saw communication errors because of (usually) one of two things..
1. because the battery had recently been disconnected. on the older OBD cars, you could clear your codes by disconnecting the battery, but the new OBDII vehicles have a re-learn period where it reruns everything to check fior errors, thus relatively elinimating the ability to wipe codes clear that way.
2. the OBD computer is going south...i have not seen it happen in a blazer or chevy, for that matter, but i have seen it happen in a focus, and in a 3000GT...

hopefully it is the first one, because the second can prove to be a nightmare...do you live in a federal emission state?

 

No, I don't live in a federal emitions state...

I thought when the battery was disconnected for a time, then the codes are reset. So I would receive a no codes message or something like that. Then after three cycles, it would then produce any codes being picked up from the sensors.

It's not that I'm not getting any codes. I'm getting a Link Error after it tries for about 30 seconds to link to the ODBII. I did a Google search on link error. And one of the most promising leads I got was that I need to flash the computer. Is that the same as a reset or a battery disonnect? Is that something I could do or do I need a technician?

Thanks for responding.

 

the flash is something done at the dealership..it usually is a reprogramming of the vehicles ECU/PCM....

 

When I purchased the vehicle I was told it was a 95. We drove away thinking it was a 95. I didn't think much more about it.

The service engine soon light comes on and we go to AutoZone. At the autozone the attendant said it was a 96. He pointed to his personal auto which was what he called a 95 and said the difference is the front ends. They were flatter.

I'm looking through the owner's manual last night and find the original sticker. Which states that the vehicle is a:

95 Blazer

So, now the question is does it even have an ODBII. Or what am I looking for? It does have a connector under the dash next to the driver's door for interfacing. But does that mean I should be able to pull codes or is it for some other (or future in 1995 like an ODBII) interface? I already know I can look under the hood for a label, but I won't be able to till sometime tomorrow

At this point on I'm looking for 95 Chevy blazer information.

I ask this because I did another google search and found that the few ODBII sites I went to refer to 96 and later vehicles, and only some 95 models being so equipped.

Also, is there some other way to pull the codes? Like with a voltmeter or switching the ignition key? I thought I heard that there was a while back, so I'm going to look into that also.

 

OK, Now I'm thinking I probably should have ensured that the AZ guy at least try an OBD I scan tool before driving away. I'm starting to think that may be the reason behind the link error.

I of course will find out as soon as I get to the vehicle.

any thoughts?

 

OBD1 in 95...it is still scanable...

 

But is it scanable with an OBDII scan tool. Or is there a difference between the scan tools?

 

No ODBII compliant statement was found on any of the labels under the hood. And the labels were all there and looked to be original. There really didn't seem to be anything obvious on any label that talked about the computer. Vacuum, AC, Coolant, all the other normal labels.

The owners manual only states that "if it is equipped with ODBII then the following may apply". Other than saying you have to look on a label under the hood for an "OBDII compliant" statement.

The connector under the dash board is a 16 pin connector. But only a few of the holes had pins in them. I'm going to look into exactly what the difference is on those pin hole counts between the two scan tools.

Does anyone already know if there is a standard number of pins in the connecter for a ODB I and II scan tools?

 

the OBDI scantool is far more primative...i would call around to some shops, like monro muffler/midas/meineke...those types to find an OBDI scanner