GM 25888305
Junction Block

One should begin replacement of the body wiring harness junction block by disconnecting the battery negative cable. The first step is to remove the driver seat followed by removal of the junction block cover. First disconnect the positive Battery Cable nut and then the positive Battery Cable from the junction block. Disconnect the electrical connectors from junction block only when yf7 equipment is installed. Liberate the junction block caged bolts completely and unlatch the tabs which secure the junction block to its base. First detach the junction block from the block base after unfastening its base nuts (1, 3). Lastly remove the wiring harness from the junction block base. To finish the process remove the junction block base which is situated on the floor. The wiring harness mounts first to the junction block base before you can install the junction block base on floor studs with caution to avoid blocking electrical connections (4, 5) beneath it. Screw in junction block base nuts onto the floor studs at 5 nm torque spec (44 lbs inch). Secure the junction block onto its base by seating all retaining tabs fully while bolt tension must reach 5 nm (44 lb in). Never omit connecting electrical connectors when using yf7 yet begin by attaching the positive Battery Cable to the junction block while installing its retaining nut and tightening it to 10 nm (88 lb in). After putting back the junction block cover, replace the driver seat followed by reattachment of the battery's negative cable.

The first step to replace the battery positive cable extension cable junction block requires detachment of the auxiliary battery negative cable. Detach both the positive extension cable nut from the junction block and disconnect the cable from its socket. Start by removing the air cleaner assembly together with the air cleaner outlet duct. The first step is removing the positive extension cable nut from the intake air heater before disconnecting both the cable and wiring harness clips. Take out the positive extension cable by first removing its nut from the ubec terminal stud and then removing the battery positive cover from the underhood bused electrical center (UBEC). The installation process requires positioning of the positive extension cable before assembly of wiring harness clips while tightening the ubec terminal stud nut to 9 nm (80 lb in). The positive cover of the ubec must be installed before the positive extension cable can be fitted to the intake air heater while tightening the nut up to 4 nm (34 lb in). Add the air cleaner assembly and outlet duct into their respective locations. You should place the positive extension cable onto the junction block before tightening its cable nut to 8 nm (71 lb in) while also reconnecting the negative Battery Cable.

Remove the fuse block center bolts and take out the fuse relay center from the junction block.

Loosen the junction block caged bolts completely and release the tabs retaining the junction block to the junction block base before removing it.

Install the battery positive cover to the UBEC.