06 TRAILBLAZER SSR 5.3L PCM ECU ECM ENGINE COMPUTER 12604791 VIN PROGRAMMING

Part Number Service NO: 12596679 and Part Number: 12604791 - Please match both of these! ECU has security and requires programming before installation. We offer FREE VIN programming so the ECU arrives and your vehicle will start once a key relearn process is completed. We will send instructions on how to complete this. During chekcout, be sure to put your VIN in the "notes to seller" field, otherwise we'll message after the purchase for your VIN. A crankshaft and throttle relearn are also recommended when replacing the ECU. A scan tool is required to complete the crank and throttle relearn. Your vehicle may not run properly if these are not completed. Be sure your mechanic is capable of completing these before purchasing. Tech Notes ECU has been tested with our state of the art vehicle simulator which tests over 25 circuits of the ECU! Some of those are listed below: All 4 O2 heaters are good! ECU powered up and has communication! ECU fuel pump relay test good! ECU A/C and st