Molex Cable

This is a Molex cable, Blue Alpine part E00102-00, at $4.58. The photo shows a thin black lead. We don’t list a pin count or length here, and that’s deliberate: with this kind of part you’re far better off matching the part number than matching a guess.

What “Molex” actually tells you

Molex is a company that makes electrical connectors, and a great many of them: wire-to-board, wire-to-wire, power, signal, in all sorts of sizes. Over the years the name turned into shorthand. Among PC builders, “a Molex” usually means the old four-pin drive power plug, which is the one the Molex connector article describes. On a parts list, though, “Molex cable” tells you roughly what kind of connector to expect, not its size or how many pins it has.

So one Molex cable and another can be completely different parts. The name alone isn’t enough to order by.

How to identify the Molex cable you need

• Part number. Look for E00102-00 in your owner’s manual or parts list. If it’s there, you’re done.
• Pin count. Count the cavities in each housing on the old cable, including any empty ones.
• Length. Measure from the back of one housing to the back of the other.
• Housing and latch. Note the color, the latch shape, and which side the latch is on.
• Both ends. Write down what each end plugs into, so the new cable goes back in exactly the same place.

Then compare with our photos. If anything doesn’t line up, photograph both ends of your old cable next to a ruler and send the pictures through our contact page. That gives us something concrete to check against.

How a Molex cable fails

Usually in one of a few ways. The latch snaps off and the plug works loose. A contact gets pushed back into its housing and no longer reaches the pin. Insulation cracks where the wire bends sharply near a connector. Or the fault comes and goes when the cable moves, which tends to mean a broken strand right at a crimp.

Any of those is a reason to replace the whole Molex cable. Re-crimping a tiny contact takes the right tool and some practice, and at this price it rarely pays.

Why pinout matters

Two cables can share the same housing and pin count and still be wired differently. Pinout is which wire sits in which position, and on a jumper it decides which pin at one end connects to which pin at the other. Get it wrong and the plug fits perfectly while the wrong signals meet. On a board, that can do real damage. It’s the main reason we tell people to order by part number rather than by appearance, and to keep the old cable until the new one is in and working.

Removing and fitting a Molex cable

Unplug the machine before opening any panel, and touch bare grounded metal before you handle circuit boards. Photograph where each end of the cable goes. Many Molex-style housings have a latch that hooks over a ramp on the mating part. Press the latch to release it, then pull on the housing. Pulling the wires is how cables get damaged in the first place.

Push the new cable on until the latch clicks, then give it a light tug by the housing. A properly latched connector won’t move. Route it along the same path as the old one, away from sharp edges and anything that gets hot. Reuse the cable ties or clips that held the old one in place.

Could a generic cable work?

Possibly, if the connector family, pin count, pinout, length and wire size all match. That’s a lot to get right for a $4.58 part, and ordering by part number is simpler. The Rev 2 power PCB board and other board-level spares are under electronics, or call +1 (443) 514-5708 if you’re unsure which Molex cable your machine uses.