This E.C.M. fits the following: 2003-05 4.2L GMC Chevrolet Trailblazer/Ext.This sale is for one service number 12574976 ECM (Engine control module) that is programmed for your vehicle
using the latest software updates using your V.I.N. (Vehicle identification number) to exactly
match your vehicle. After you purchase the E.C.M. you will need to provide us with your V.I.N so that
we can program the E.C.M. before we ship it to you.This computer is refurbished and tested for functionality. There is no core charge you keep your old E.C.M. There is a one year replacement warranty.Two things may have to be done after you install your E.C.M. First an anti-theft
relearn may have to be performed. If this is the case the truck will not start.
The second thing is that a crankshaft variation relearn may need to be performed once the vehicle is
running. This will be evident if the check engine or service engine soon light comes on once the vehicle
is running. You will need access to a scan tool capable of doingthis procedure to do this and clear any related
trouble codes (Code P0315 or P1336). If this is not available to you a repair shop will have to perform this and clear the
related trouble code. The vehicle will run normal but the ”service engine soon” light will come on and a
trouble code will be stored until this is resolved.Instructions for both procedures will be included.We will ship within one business day of payment.Same day shipping if ordered by 2:00 EST (Mon. - Fri.)
