GM Instrument Cluster Bench Test Harness ($35.00 + S&H)


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I've been spending that last day or so Beating The Living Hell out of an idea for making a GM Instrument Cluster Bench Test Harness to interface the "GYMKO" Tech2 Scanner for the purpose of Post Repair Testing of the Cluster Dial Sweeps and the Instrument Panel LEDs ...when I stumbled across THIS:

There is an option at Checkout to purchase its own 12 VDC Power Supply, but that is easy enough to solve in so many other ways as well, Other than having a S&H Fee that is a bit steep at around $14.00 ... I doubt that I would have been able to do any better. While I can still use the "GYMKO" Tech2 Scanner to perform more extensive Tests of The Cluster if needs be by simply plugging it right back into the SUV Cluster harness Connector before completely assembling the components back inside of the casements... THIS handy thing will allow for Bench Testing it Before and After doing any repairs that will involve simple Repetitive Dial Sweeps and eye balling all of the Dash Light LEDs for proper working order...or burnouts... and NOT have to run back and forth to the Truck to perform these same tests:

These come in Two GM Flavors:



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The product is sold out and no one answers the phone or returns emails. Can someone on here build one for me?


The radio harness uses the same connector as the instrument cluster. So you can buy a replacement pigtail, and use that for your test bench. That's what I did years ago when I swapped LEDs into my cluster and wanted to be able to test it outside of the vehicle.



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Any Power Supply having 110-120 Volts AC In --> and 12 Volts DC Out @ 1 Amp will Suffice (fusing the Power In Wire with a 2 Amp fuse could not hurt) and you can add in a simple On/Off Toggle Switch if you wanted to get Fancy. Here is the Instrument Panel Cluster Connector Wiring Diagram linked above courtesy @Blckshdw:


Often... it can be Difficult to Confirm the Voltage Polarity on Common AC to DC Power Supplies. This Instructional Video shows how to sort that problem out using a Digital Multi-Meter AFTER Taping down the Two Leads from the PS to a piece of cardboard... lest they 'magically' touch each other while wrangling with the Red & Black Probes on the open copper wire ends. Label the (+) Wire afterwards if the PS is not being immediately soldered into the Connector Harness (+) Wire and (-) Ground Wire locations:

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Or cheaper still, go to a pick-n-pull and get yourself some, likely for free. That's what I used. Get them for the radio, PCM, BCM, cluster, etc.

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