Cant Read ECU after EFI Live Flash

[akcooper9]

I picked up an OBD2 adapter to stream data to the smarty phone. The adapter works great on my bone stock 01 2500hd 6.0 but on my efi live tuned 02 2500hd 6.0, I can not get it to connect to the ecu. I've also tried this reader (http://www.autozone.com/autozone/accessories/Actron-OBD-II-code-reader-for-1996-and-newer-vehicles/_/N-25iq?itemIdentifier=603853&_requestid=6358292) and again, it powers up but wont connect. I've checked the CIGAR fuse and its good along with power at the DLC.

FWIW, I did not tune the ECU my self. I had a reputable tuner tune it.

Any thoughts or suggestions? Is the ECU locekd?

Thanks

[Boost]

Locking the tune should not prevent you from connecting to the PCM.

[akcooper9]

Locking the tune should not prevent you from connecting to the PCM.

Well that is good to know. Now the question becomes is why wont it connect/read? And how do I fix the issue?

[joecar]

I picked up an OBD2 adapter to stream data to the smarty phone. The adapter works great on my bone stock 01 2500hd 6.0 but on my efi live tuned 02 2500hd 6.0, I can not get it to connect to the ecu. I've also tried this reader (http://www.autozone.com/autozone/accessories/Actron-OBD-II-code-reader-for-1996-and-newer-vehicles/_/N-25iq?itemIdentifier=603853&_requestid=6358292) and again, it powers up but wont connect. I've checked the CIGAR fuse and its good along with power at the DLC.

FWIW, I did not tune the ECU my self. I had a reputable tuner tune it.

Any thoughts or suggestions? Is the ECU locekd?

ThanksCan you connect to your truck using the V7 scantool or V7 tunetool...?

Do you have FlashScan V1 or V2...?

[akcooper9]

I would assume so because the truck was tuned with efi live. But I personally dont have a V2 or have access to 1. I do have an email out to my tuner.

I more or less need to solve the problem before smog time...

[joecar]

The ALDL connector may have a broken wire or loose pin.

[akcooper9]

How do you recommend going about testing it? I checked Pin 16 for power and 4 & 5 for ground. I wasnt sure how to check the other two pins.

[joecar]

You would have to disconnect the battery, unplug the PCM from the harness, check for continuity of the serial data line between the ALDL and the PCM connector.

Also, you need a wiring diagram (for your year/model/vehicle) which shows all the other modules on the serial bus...

there is a splce connector where all the serial lines join together from all the modules...

the splce connector is removable, you should check continuity between here and the ALDL connector;

also with all the other modules unplugged from the harness, at the splce connector check each serial line for short to power or ground.

[joecar]

What year/model/vehicle do you have...?

What state are you going for smog test...?

[akcooper9]

Man that sounds like a pain! I just walked out to the truck. The two pins I did not check was 2 and 14

Where do I find a wiring diagram?

[akcooper9]

What year/model/vehicle do you have...?

What state are you going for smog test...?

2002 Chevy 2500HD 6.0 gasser

CA

[joecar]

I may be able to find a wiring diagram for that later today.

[akcooper9]

Sounds good. I appreciate the help!

[akcooper9]

I tried the Actron OBD2 reader I have again after reading the directions and it worked just fine. Im starting to think the ELM327 adapter is junk and or doesnt like my truck.

Ill be sending it back for a replacement. Ill Keep you guys posted.

[joecar]

I was not able to find the right schematic... I'll try again today.

[akcooper9]

Update: I sent the reader back and purchased a different unit. The new reader works great. Sorry for the worthless thread. Appreciate all the help.

[joecar]

No worries, glad you got it sorted out.