fuse box junction box swap/replacement?

2003 CHEVROLET TRAILBLAZER
175,000 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC
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WBJMS56
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I have the vehicle listed above with the in-line six-cylinder. The fuse box is gone dead will any other year of fuse box work with a 2003 like a 2004 possibly. I have a 2003 coming from eBay, but I’m just curious since they don’t change certain parts on cars, and they might use the same part on three or four different years of the same car or any other fuse box work with this car.
Mar 25, 2024 at 3:51 PM
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CARADIODOC
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The best way to figure out what else will work is to look in a Hollander guide at any salvage yard. The problem is the same box might be used for multiple years, but there may be missing or extra unused terminals for optional systems. You're better off just finding the same box from the same model and year, with the same engine, in a salvage yard.

Be aware a totally dead fuse box is an extremely common problem on any brand and model. It's caused by a loose or corroded nut attaching the smaller positive battery wire to the box. The fix can be as simple as tightening that nut, or as involved as removing the terminal to clean and shine it up. Before you do that, we like to know for sure we've identified the correct cause of the problem. To do that, turn on the head lights or anything else so current is trying to flow. That's needed to make the following voltages show up.

Use a test light or a voltmeter to measure the voltage on the terminal at the end of that positive wire, (not the stud or nut). You'll find 12 volts on that terminal. Now move the probe a fraction of an inch to the stud. If you find 0 volts, or considerably less than 12 volts, that connection needs to be cleaned or tightened.

The same symptom can show up if the smaller negative battery wire is loose or rusted off where it bolts to the body sheet metal. In this case you can still have 12 volts on the fuse box, depending on where you place the ground lead for your voltmeter or test light.
Mar 25, 2024 at 4:50 PM