LS Gen 3 ECM Engine Programming Control Module Reader Diagnostic PCM Bench Harness w/Power Supply Fits for GM Chevy All Blue/Red & Blue/Green 1999-2007, OBD2 Port, 18 Gauge, 12 Volt

5 stars because it does what it's intended. However, check the wiring before using.Mine was wired in reverse polarity, therefore, would not work.Furthermore, the ground pin was in the wrong spot and needed to be moved to pin one. I referred to the sloppy mechanics wiki to get the proper pin connections.Additionally, the connector to the PCM is pretty cheap and doesn't fit great.Lastly, this works just fine and does exactly what you expect it to do. I was able to read and write without upgrading the power supply though I was fully prepared and okay with doing so.UPDATE 4-16-2024,I ended up upgrading to a larger power supply as the one supplied would not work on the P59 pcm. If your on a 512 P01 pcm it should work but be ready to upgrade the power supply potentially.

Power was connect to ground and ground to power. The ground pin is in the wrong location, you will have to pin it to #1. The supplied power supply is not strong enough to support writing to the PCM. Found an old firetv power supply and that was able to get the harness to both read/write.

Works as intended when using HP tuners to Bench flash P01/P59 411 PCM's.Recommend double checking power supply wires are going to correct polarity based on other reviews but mine was correct out of box. Would recommend, saved me time over making one, well worth the $36 it costs.

A wire was in the wrong pin location

It is cheap but it can work. I found that they wired mine right but the power supply is too weak. It would only read with my wireless OBDlink MX, it wouldn't write. I switched out to a better 12 volt power supply and my OBDlink still wouldn't write. I had to use an OBDX Pro wired or HP tuners wired to get it to write. LS droid says the computer should be at 13 volts and I see folks recommending the Belker 45w Universal power supply for clean power to write. I am going to order one and see if my OBDlink MX will work on wireless.It isn't a bad deal but know that the power supply (which looks the same as the another more expensive ones on Amazon) will need to be replaced. There also isn't a switch to turn the computer on and off for the key cycle. But it is cheap....

So first it didn't work, being a tuner and mechanic I wanna check for proper voltage or shorts. First I have no voltage where I should so I remove electrical tape to find both connections from the power supply to be uninsulated crimps laying against each other then taped. Positive touching negative. Then the ecu ground pin was in the wrong location. Not 1 location off but 20 from the right one. Then the diagnostic port was pinned backwards. So if you was looking at the backside and counted left to right it was correct, but that's not how it's layed out. Plus THERES NUMBERS ON THE DIAG PORT. no doubt the dyslexic, Chinese 12 year old assembled this was under the influence of alcohol and poor quality methamphetamine. Just buy the connectors and build your own.

If you buy one of these. Please that the tape off. This is how I found mine right out of the box. It was all taped together and not separated. They was touching together. But I only took mine apart to splice in and use a 12 volt 5 amp and I had read the other reviews and seen this. Haven’t tested it yet. Will be doing it tomorrow. Hope this helps someone. I’ll leave more feedback after the test.———— Update this thing works great. After fixing it.

I did a fan conversion swap on a 2003 Tahoe. I was receiving issues with trying to flash the ecm while on the truck. Once I received this bench harness I was able to flash the truck and reinstall the ecm within minutes. My only issues was the plastic retainer that holds the blue caps on the connector won’t stay on, I think the little tab on the retainer is broken off or worn down. The cap stayed inside the ecm but I just flipped it over and it came right out. For the price and the convenience that this adds I would and will recommend it to anybody I know. Thank you again!