LS Gen 3 ECM Engine Programming Control Module Reader Diagnostic PCM Bench

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.

I bought this harness to power up and reflash the PCM from a 1999 1500 truck with a 5.3 LS engine, and it worked exactly like I needed it to. I used it as a bench harness with my laptop and tuning/programming equipment. The PCM powered up properly, connected without any issues, and I was able to complete the reflash successfully. This saved me from having to build my own temporary wiring setup or install the PCM in the vehicle just to program it. For anyone working with an early Gen 3 LS truck PCM and needing a simple way to power it on the bench for flashing, tuning, or diagnostics, this is a very handy harness. Mine worked right out of the box and did exactly what I bought it for.

don't listen to all the bad reviews !, this baby worked perfect out of the box for p59 2004 silverado HP Tunners plenty of power dont know what the other guys using this plugs into wall better than a batt , god speed -

Its an ok setup but needs two improvements. For P01/P59 1. Needs a better power supply During reading the one provided is ok. During writing it does struggle and can corupt programming. I prefer a stable voltage of 13.8V to 14V so use a power supply that has CV (constant voltage). And no this is not to much voltage. You have to remember when the engine is running the charging system puts out 13V to 14V roughly depending on electrical load. 2. Your pins are 19 20 59 and 60. They have 59 in 58 cavity. Wire 58 needs to be moved to 59 cavity. I give it four stars at least. The C1 connector alone is worth the purchase if you dont want to purchase a used C1 connector. 19 = pink +12V switched 20 = orange +12V constant 59 = yellow class 2 data 60 = black - ground

Worked Flawless. No extra steps just plug in and flash away!

I purchased this so I could do off-board programming on a GM PCM (2005 Silverado 5.3.) The power supply was too small, most of the wires did not make it into the crimps, and the Ground wire did not connect to any of the ground pins of the PCM. Moving the ground, soldering all of the connections and jumper wiring it to a battery it almost worked. After programming, if you completely remove the power, the software stays but the VIN doesn't lock in, so I had to add a switch to the ignition lead, now it works fine. So really, I used the PCM connector and the DLC only, but I did get my truck done.

As expected, the wiring was incorrect. The ground wire that should go in pin 1 of the pcm connector was in pin 60 (throttle position low reference). The obd connector side was correct. I bought it knowing to check for bad wiring and expecting to need to use a better power supply, but for the price it was worth it to me. I will of course also be wiring in a switch on the ign + wire, instead of just connecting it to the always hot +12v.

Worked as promised .

Muy practico!

I was a bit hesitant after reading a few negative reviews, but the unit I received works perfectly. I checked for the issues others mentioned—Pines in wrong order, and bare connections—and mine had none of those problems. Build quality seems solid, and it's doing exactly what it’s supposed to. Glad I took the chance on this one.

Better off buying else where, Didn't come when it was suppose to, and on top of that computer doesn't read...... faulty crap.

Tried it out as soon as I got it. Wouldn't power up any computer. Did get it to work after un-taping the harness they had and separating the ,+ve and -ve power wires

Had to completely re-wire. Came with power supply positive and ground reversed as well as ground pin in incorrect location. Very poor quality product.