Copy PCM to swap in a new one with Tech 2?

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mattbta

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Hopefully they approve my account soon. I'd love to share what happened. I couldn't' find any posts with similar issues.

I used PCM Hammer v21. Tried searching for older versions but wasn't having much luck.
It took a while for mine. PM me your requested username and I can send a nudge to the admin.

Mind sending over the logs or posting here? Curious to see the output logs of the read that borked the VATS.
 
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Matthew Jeschke

Matthew Jeschke

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I fried my PCM years ago in my 1994 Z28. Had to send it out to get it redone. That said, HP tuners is awesome. Never had slightest issue but I make sure laptop is well charged (even plugged in) and the battery is good.

Seems PCM hammer may not be fully tested.
 

Mudsport96

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I fried my PCM years ago in my 1994 Z28. Had to send it out to get it redone. That said, HP tuners is awesome. Never had slightest issue but I make sure laptop is well charged (even plugged in) and the battery is good.

Seems PCM hammer may not be fully tested.
I've used pcm Hammer a couple times. I usually use LSDROID with no issues at all
 
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Matthew Jeschke

Matthew Jeschke

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I cannot for life of me get a bench programmer to work. Where am I going wrong...

Blue connector C1 & OBD2 Connector

GROUND: PCM Pin 1, OBD2 Pin 4 & 5
12.6v: PCM 20, OBD2 16
12.6v switched: PCM 19
Serial Data: OB2 2, PCM 58

I'm using DC power supply. PCM is pulling 0.39A @13.1V

PCM hammer will not connect though. I have connected through USB then Select Device->J2534 Device Type "VXDIAG".

I watched several YouTube tutorials and seems to be what they have setup.

UPDATE ABOVE IS CORRECT just my luck, I had a bad USB cable. Swapped USB cable and worked.
 
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Matthew Jeschke

Matthew Jeschke

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I hotwired the PCM to the cluster. Monitored VSS Output with Oscope, as well as used a scan tool to see what computer said speed was. I then sent a sine wave in for the VSS input.

Everything worked like a champ BUT the cluster. I am searching for a new cluster now...

Will that Tech 2 win allow me to update the mileage on the new cluster? Any ideas... maybe I need a new thread.
 
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Matthew Jeschke

Matthew Jeschke

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Cool, I think I see on the pinout for the harness that there's a serial data line. I assume I hook the scan tool up to that serial data line and power the cluster...

Last cluster I did wasn't one of these newer style. It didn't have any serial data line.
 
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Matthew Jeschke

Matthew Jeschke

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Well I was successful in cloaning my PCM. Unfortunately, PCM wasn't the issue. It's the cluster that's gone bad. Having a heck of a time finding a new instrument cluster for a 1999 C5 Corvette Hardtop though. It dawned on me though, even when I get a new cluster I'll need to update it with my VIN and mileage. I'm assuming Tech 2 Win can help with programming a cluster?

I may try and fiddle w/ the software as I see not faults (visual inspection) on circuit board in cluster. Maybe the software just got corrupted.

Any idea on how to hook-up the scan tool to the cluster? I assume I just power the cluster, the scan tool, and connect the serial pin to the serial pin on the scan tool?
 

Fless

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FWIW a Tech 2 isn't able to program mileage to a different cluster, at least not on my '04. Are you sure the 'Vette mileage is in the cluster?
 

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