GM 25906446
Junction Block

The first step to change an underhood electrical center or junction block starts with hood opening while supporting it and disconnecting the negative Battery Cable. The cover from the accessory wiring junction block base must be removed before unthreading the positive cable nut to access the positive terminal stud. After releasing the two locking tabs from the electrical center base you can gradually lift the accessory wiring junction block assembly to let it depart from the three main harness connectors and view the lower connectors. A hook tool should be used to pull the connector upward and reposition all 3 lower harness connectors into the base before installing the new assembly. Validators should confirm that all 3 connectors have appropriate seating by pressing lightly on the base while checking for tab engagement on each side. Placement of the new underhood accessory wiring junction block assembly should begin with proper alignment of its locator pins before applying downward pressure to secure it to the base. Two outer locking tabs on the assembly must be checked for proper connection into the lower base. Fasten the positive Battery Cable across the stud while tightening its retaining nut until it reaches 10 n.m (89 lb in). Afterwards install the underhood electrical center cover onto the electrical center base by reconnecting the negative Battery Cable while closing the hood and performing power sliding door re-initialization.

Starting the instrument panel electrical center or junction block replacement procedure requires disconnecting the negative Battery Cable. First step involves removing both the instrument panel right side endcap cover alongside the i/p compartment. The procedure starts by unfastening the i/p accessory wiring junction block assembly from the i/p carrier through the removal of its 2 forward screws. Then remove the 2 nuts that secure the assembly bracket to the i/p carrier. Lower the bracket that contains electrical centers from the instrument panel before swinging the junction block inside the compartment area. You should press and release the retaining tabs from the shroud/base before disconnecting the electrical connector from the i/p wiring harness then extract the i/p accessory wiring junction block assembly from the connector. Before installing the new i/p wiring harness junction block always re-stage all the connectors into the lower i/p accessory wiring junction block assembly base/shroud while making sure the main harness is locked in position at the lower shroud/base. To install the harness connectors should be firmly attached to retention tabs before positioning the connector to the i/p wiring harness junction block and gently pushing the connector against the base until both external locking tabs secure. Secure the extra i/p connectors after positioning the bracket and bracket studs on the carrier then install the nuts before tightening them to 10 n.m (89 lb in). Secure the 2 screws at the i/p endcap by tightening them to 2 n.m (18 lb in). The i/p compartment and i/p right side end cap cover installation must be completed before reattaching the negative Battery Cable. The power sliding door re-initialization process should be completed last.

Ensure the main harness is secured into the lower shroud/base.

Remove the instrument panel right side endcap cover and the I/P compartment.

Carefully lift each side to release it from the 3 main body harness connectors, exposing the lower connectors.

Position the connector to the I/P wiring harness junction block and carefully squeeze the connector to the base until both outer locking tabs are secure.

Inspect the 2 outer locking tabs.