5.3L no connection

I have EFILive Flashscan V2 and for some reason it will not let me into the ecm on my 99 Silverado. Has anyone ever had this issue?

Hello KSL667,

The ’99 5.3L in your truck has “Vortec” on the engine cover, but it’s a Gen III V8 for the purpose of this forum – lots of good info in that section of the Forum.

In the Scan Tool go to Edit\Properties\Connections …….. select the check box to “Scan for all cables” … and set your default to EFILive FlashScan V2.5 (HAPI).

Sometimes when you update the software, these settings get changed.

Hopefully that helps ….


Regards,
Taz

Thank you Taz

I have EFILive Flashscan V2 and for some reason it will not let me into the ECM to either pull the stock tune off or install another tune on my 99 Silverado, but I can get into the ECM with the scan tool. Has anyone ever had this issue?

I merged/moved your two threads, which is why post #4 shows up after Taz's response.

Hello KSL667,

Glad to hear you got the ScanTool to connect - at least you know it's not an equipment issue ! What happens, or what message / error do you receive when trying to read your PCM's tune ?

Regards,
Taz

When it is loading down the screen, it says something like Found ECM, Connecting to ECM, Disconnected from ECM. It does that for all 6 things it trys connecting too. Then the V2 Scan box will freeze and I have to unplug it from the pickup to restart the V2 box. It will read and connect to the LMM Duramax fine though. I tried using the 97-98 LS1 gen III, 99-07 LS1 gen III and neither worked. about twenty times a piece. The 99-07 one works with the scan tool part though

Hello KSL667,

Sorry for the delay in follow up ….

To recap:

• changes to the connections settings in the Scan Tool got that working for your ’99 truck
• you were successful in reading a Duramax PCM
• when trying to read the PCM in your ’99 5.3 L Silverado - the software locates the PCM, then connects and disconnects several times - then the software “freezes”

You mentioned trying both the LS1-A (97-98) PCM and LS1-B (99-07) PCM, as the controller in the drop down box - neither worked.

The PCM selected in the controller drop down box tells EFILive what unlocking strategy to employ - make sure you select your particular PCM (I know it didn’t work either way last time).

Would you check the Tune Tool to see what version / build you have ? In the Tune Tool under the “Help” menu click on “About” and then “Version”.

Wondering if you need to update the software – there have many changes recently.

This type of problem is not my area of expertise. I can file fit piston rings blindfolded, but the IT department I’m not !


Regards,
Taz

Good point...

which versions of V7/V8 software and which V2 firmware version...?