Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2008 Chevrolet Chevy Express G3500, Van Passenger ExtendedFACTORY OEM SERVICE PROCEDURE
Installation Procedure
- Install the junction block base by sliding tabs (2) in and pressing in tabs (1) until they are locked.
- Install into the junction block base the Chassis Harness (1), the I/P Harness (2), the Engine Harness (3), and the Forward LP Harness (4).
- Install the fuse relay center into the junction block.
- Install the fuse block center bolts.
- Install the harness ends on the fuse block relay center.
- Install the harness end nuts (2).
- Install the junction block cover (1) the tabs (3) should lock.
- Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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