mattbta
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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.
Copy PCM to swap in a new one with Tech 2?
- Thread starter Matthew Jeschke
- Start date
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Mind sending over the logs or posting here? Curious to see the output logs of the read that borked the VATS.
Mudsport96
Full Access Member
This here is why I ONLY USE a bench harness for flashing. A slight glitch, miscommunication between bcm and pcm, or voltage fluctuation can nuke a pcm.
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Matthew Jeschke
Full Access Member
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.
Seems PCM hammer may not be fully tested.
Mudsport96
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I've used pcm Hammer a couple times. I usually use LSDROID with no issues at all
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Matthew Jeschke
Full Access Member
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.
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.
Last edited:
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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.
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.
It Should. Or at a minimum copy old reading.
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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.
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
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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?
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?
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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Matthew Jeschke
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Yes positive it's in the cluster. I can power up just the cluster and it shows the mileage.
Is there a tutorial or something on PCM hammer for programming clusters?
Found the code https://github.com/mikebb203/IPC-Hammer
Is there a tutorial or something on PCM hammer for programming clusters?
Found the code https://github.com/mikebb203/IPC-Hammer
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Matthew Jeschke
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I tore apart my cluster again... Bench tested it with a 10vpp square wave going to the speedometer pin A7.
Removed all modules not related to the gauge to see if one was interfering.
I also gently pressed on the board in various spots to see if possibly a trace or via broke or delaminated.
Additionally, I probed the square wave to see if something was corrupting the input. It's clean at least at the header.
Still have same issue, speedometer will not respond.
I see there's a serial data pin on the cluster. I tried wiring that directly up to the VX nano adapter.
I wondered if I could do anything with Tech 2 or PCM hammer to scan the cluster, maybe the software on it just got corrupted? Or if I have to have the cluster installed in the vehchile w/ PCM and other computers to communicate with the cluster?
Removed all modules not related to the gauge to see if one was interfering.
I also gently pressed on the board in various spots to see if possibly a trace or via broke or delaminated.
Additionally, I probed the square wave to see if something was corrupting the input. It's clean at least at the header.
Still have same issue, speedometer will not respond.
I see there's a serial data pin on the cluster. I tried wiring that directly up to the VX nano adapter.
I wondered if I could do anything with Tech 2 or PCM hammer to scan the cluster, maybe the software on it just got corrupted? Or if I have to have the cluster installed in the vehchile w/ PCM and other computers to communicate with the cluster?
mattbta
Full Access Member
I was looking for a radio bench harness and stumbled across this and filed it away for later. Not sure if it applies to a 99 though.
gmtnation.com
SOLVED! - How to Make A "GYMKO" Tech 2 Bench-Top Test Harness
I'm sorry if this Topic has been neglected by me since March 20th, 2018... but there always seem to be other more pressing projects and repairs that must supersede a project like this that, while interesting for the sake of exploring these ideas and possibilities... are not absolutely necessary...
gmtnation.com
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Matthew Jeschke
Full Access Member
@mattbta thanks! I'll go through it 
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Matthew Jeschke
Full Access Member
Welp I was able to wire up the VCX Nano to the instrument cluster. I think it is working, but the PCM Hammer for IPC isn't compatible with whatever is on this cluster form the looks of it. Unless I did something wrong. I simply did Pin 2 OBD2 connector to Pin A11 on the cluster for serial data. Then of course powered everything up. For sake of completeness I have the PCM also hooked up.
I'm now trying to use this Tech2Win to see what I can do with it for self checks. Confused though...
What do I select here? Seems to make no difference either way...
This screen is just blank... I cannot get it to populate with anything.
If I click cancel it will bring up Tech2Win but only allows year 2003 or 2002 for Chevrolete? My corvette is a 1999
I'm now trying to use this Tech2Win to see what I can do with it for self checks. Confused though...
What do I select here? Seems to make no difference either way...
This screen is just blank... I cannot get it to populate with anything.
If I click cancel it will bring up Tech2Win but only allows year 2003 or 2002 for Chevrolete? My corvette is a 1999
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